Safety-related issues resulting in labelling amendments made to the local package inserts are listed below. Please note that there might be lag time in the availability of the package insert which reflect the latest change(s). Please refer to the company representative for details.
 |
December 2007
- Bromocriptine (Parlodel®, Novartis) New ADR: Cardiac valve fibrosis.
- Cabergoline (Dostinex®, Pfizer) Contraindications: History of pulmonary, pericardial & retroperitoneal fibrotic disorders. Anatomical evidence of cardiac valvulopathy of any valve (e.g. ECG showing valve leaflet thickening, valve restriction, valve mixed restriction-stenosis).
Special warnings/precautions: Erythrocyte sedimentation rate (ESR) found to be abnormally increased in association with pleural effusion/fibrosis. Chest x-ray examination is recommended in cases of unexplained ESR increases to abnormal values. Serum creatinine measurements can be used to help in the diagnosis of fibrotic disorder.
All patients recommended to undergo cardiovascular evaluation, including an ECG, to assess potential presence of an occult valvular disease before initiating treatment with cabergoline. Subsequent regular clinical diagnostic monitoring (e.g. physical examination, x-ray, ECG, CT scan) for development of valvular disease or fibrosis is recommended.
Undesirable effects: The prevalence of asymptomatic valvular regurgitation is significantly greater than that of non-ergot dopamine agonists. - Drotrecogin alfa (Xigris®, Eli Lilly) Warnings:
-Prophylactic heparin should not be discontinued unless considered medically necessary. In a randomized study of prophylactic heparin vs placebo in 1935 adult severe sepsis patients treated with Xigris®, mortality & rate of serious adverse events were increased in the subgroup of 434 patients whose low-dose heparin was stopped on study entry by randomization to placebo.
Drug interactions:
-Low-dose heparin for venous thrombotic events prophylaxis may be co-administered with drotrecogin alfa. There was no increased risk of bleeding, including CNS bleeding. Prophylactic heparin increased the risk of non-serious bleeding. - Norelgestromin/ ethinyl estradiol (Evra®, Johnson & Johnson) Interaction: Hormonal contraceptives may interact with bosentan.
New ADRs: Blood cholesterol abnormal, blood glucose abnormal/ decreased, low density lipoprotein increased, cerebral haemorrhage, haemorrhage intracranial, haemorrhagic stroke, migraine with aura, subarachnoid haemorrhage, dermatitis allergic, exfoliative rash, photosensitivity reaction, hyperglycaemia, insulin resistance, fibroadenoma of breast, uterine leiomyoma, cervical dysplasia, hypomenorrhoea, breast mass, menometrorrhagia, oligomenorrhoea, suppressed lactation, emotional disorder, insomnia. - Risperidone (Risperdal®, Johnson & Johnson) Special warnings:
As with other antipsychotics, caution should be exercised when Risperdal® is prescribed in patients with a history of cardiac arrhythmias, congenital long QT syndrome & in concomitant use with drugs known to prolong the QT interval.
Clinically significant hypotension has been observed postmarketing with concomitant use of risperidone & antihypertensive treatment.
New ADRs: URTI, UTI, anaemia, dyspnoea, epistaxis, seborrhoeic dermatitis, arthralgia, blood creatine phosphokinase increased, pneumonia, confusional state, transient ischaemic attack, conjunctivitis, faecaloma, agranulocytosis, thrombocytopenia, anaphylactic reaction, diabetic ketoacidosis, mania, atrial fibrillation,sleep apnea syndrome, intestinal obstruction, jaundice, ECG QT prolonged. - Strontium ranelate (Protos®, Servier) Special warnings & precautions for use:
Cases of severe hypersensitivity syndromes, including, in particular, drug rash with eosinophilia & systemic symptoms (DRESS), sometimes fatal, have been reported with the use of Protos®. DRESS syndrome is characterised by rash, fever, eosinophilia & systemic involvement e.g. adenopathy, hepatitis, interstitial nephropathy/ lung disease. Time to onset was usually around 3-6 weeks. Recovery could be slow & recurrences of the syndrome have been reported in some cases after discontinuation of corticosteroid therapy.
Patients should be informed to stop Protos® immediately & permanently when a rash occurs & to seek medical advice.
Patients who have stopped treatment due to hypersensitivity reactions should not re-start therapy with Protos®.
Treatment with Protos® should be discontinued in case of serious allergic reaction.
New ADRs: Vomiting, abdominal pain, oral mucosal irritation including stomatitis &/or mouth ulceration, rash, pruritus, urticaria, angioedema, SJS, drug rash with eosinophilia, DRESS, muscle spasm, myalgia, bone pain, arthralgia, pain in extremity. - Terbinafine HCl (Lamisil® tablets, Novartis) Special Warnings & Precautions for use:
-Aetiology of any very rare cases of blood dyscrasias (neutropenia, agranulocytosis, thrombocytopenia, pancytopenia) that occur in patients treated with Lamisil® tablets should be evaluated & consideration should be given for a possible change in medication regimen, including discontinuation of treatment with Lamisil® tablets.
-Lamisil® tablets has not been adequately studied in renal impairment & therefore not recommended.
-Serious skin reactions (e.g. SJS, TEN) have been very rarely reported in patients taking Lamisil® tablets. If progressive skin rash occurs, Lamisil® tablets should be discontinued.
-Very rare cases of serious liver failure (some with a fatal outcome, or requiring liver transplant) have been reported in patients treated with Lamisil® tablets. In the majority of liver failure cases, patients had serious underlying systemic conditions & a causal association with the intake of Lamisil® tablets was uncertain.
No studies on the effects of Lamisil® tablets treatment on the ability to drive & use machines have been performed. Patients who experience dizziness as an undesirable effect should avoid driving vehicles or using machines.
New ADRs: Pancytopenia, dizziness, paraesthesia & hypoaesthesia. - Zolpidem (Stilnox®, Sanofi-Aventis) Pregnancy: Insufficient clinical data are currently available concerning exposure during the 1st trimester of pregnancy.
-In view of available data, it is preferable, as a precautionary measure, not to use zolpidem at any stage during pregnancy.
-If it is necessary to initiate treatment with zolpidem towards the end of pregnancy, prescription of high doses should be avoided & signs of impregnation, respiratory depression, apnea, hypothermia, withdrawal syndrome should be taken account of when monitoring the neonate.
New ADRs: Hallucinations, somnambulism.
|
November 2007
- Budesonide (Rhinocort aqua®, AstraZeneca) Pregnancy & lactation: Compared to expected incidence, a small increase in the occurrence of minor heart malformations has been detected in children where the mother has been exposed to Rhinocort aqua® in early pregnancy, however a relationship to the exposure is not likely.
During pregnancy, the aim must be the lowest effective dose & the shortest treatment period of Rhinocort aqua®.
Treatment with Rhinocort aqua® in women who are breastfeeding should only be considered if the expected benefit to the mother is greater than any possible risk to the child. - Cefuroxime sodium (Zinacef®, GSK) Warnings & precautions:
-As with other antibiotics, use of Zinacef® may result in the overgrowth of Candida. Prolonged use may also result in the overgrowth of other non-susceptible organisms (e.g. enterococci & Clostridium difficile), which may require interruption of treatment.
Interactions:
-Zinacef® may affect the gut flora, leading to lower oestrogen reabsorption & reduced efficacy of combined Ocs.
New ADR: Cutaneous vasculitis. - Fluoxetine (pms-fluoxetine®, IDS) Contraindications:
-Thioridazine should not be administered concomitantly with pms-fluoxetine or within a minimum of 5 weeks after pms-fluoxetine has been discontinued, nor should pms-fluoxetine be administered within 2 weeks after thioridazine has been discontinued.
Warnings:
-Not for use in children under 18 years of age.
-Patients may experience unusual feelings of agitation, hostility or anxiety, or have impulsive or disturbing thoughts such as thoughts of self-harm or harm to others, particularly in the first few weeks or when doses are adjusted.
-Particular caution should be exercised in patients with a history of allergic reactions.
-Antidepressants increased the risk compared to placebo of suicidal thinking & behaviour (suicidality) in children, adolescents & young adults in short-term studies of major depressive disorder (MDD) & other psychiatric disorders. There was a reduction in risk with antidepressants compared to placebo in adults aged 65 & older. Depression & certain other psychiatric disorders are associated with increases in the risk of suicide. Patients of all ages who are started on antidepressant therapy should be monitored & observed for clinical worsening, suicidality or unusual changes in behaviour. Families & caregivers should monitor these patients.
Use in pregnancy & lactation:
-Post-marketing reports indicate that some neonates exposed to fluoxetine, SSRIs or other newer anti-depressants, late in the third trimester have developed complications requiring prolonged hospitalization, respiratory support & tube feeding (see Warnings & Precautions).
-The potential risks & benefits of treatment with pms-fluoxetine in pregnant women during the third trimester should be considered carefully. Tapering of pms-fluoxetine may be considered.
Precautions:
Caution should be exercised before starting pms-fluoxetine in patients with/on:
-Medical conditions, including a history of liver or kidney problems, seizures or blackouts, diabetes & heart problems or abnormal bleeding.
-Any natural or herbal products (e.g. St. John's Wort).
-Habits of alcohol &/or street drug consumption.
-A need to drive a vehicle or perform hazardous tasks during work.
It is stated that a lower or less frequent dosage should be used in patients with renal &/or hepatic impairment & in those on multiple medications.
Drug Interactions:
-Pms-fluoxetine is not to be used if patient is taking or has recently taken MAOIs or thioridazine.
-Care should be taken if patient is taking or has recently taken the following:
-Other anti-depressants, such as SSRIs, certain tricylics, drugs used to treat schizophrenia, or bipolar depression (e.g. lithium)
-Drugs which may affect blood clotting & increase bleeding, such as blood-thinning drugs (anticoagulants, e.g. warfarin) as well as acetylsalicylic acid (e.g. aspirin) & other NSAIDs (e.g. ibuprofen)
-Certain medicines used to treat irregular heart beats
-Certain drugs used to treat diabetes
-Other drugs that affect serotonin, such as lithium, linezolid, tramadol, drugs containing tryptophan, St. Johns Wort, triptans used to treat migraine
-Sedatives such as benzodiazepines
Concomitant use of fluoxetine in patients taking pimozide is contraindicated.
There have been rare reports of prolonged seizures in patients on fluoxetine receiving ECT treatment.
As with many drugs that work directly on the brain, use of alcohol while taking pms-fluoxetine should be limited/moderate.
New ADRs: Upset stomach, anxiety, weakness, loss of appetite.
Pms-fluoxetine does not usually affect people's normal activities but some people feel sleepy while taking it hence these people should not drive or operate machinery.
-Although psychiatric disorders may be associated with decreases in sexual desire, performance & satisfaction, treatment with pms-fluoxetine may also affect sexual functioning.
-Care should be taken if stopping pms-fluoxetine as symptoms such as headache, insomnia, paraesthesias (numbness, tingling, burning or prickling sensation), nervousness, anxiety, nausea, sweating, dizziness, jitteriness & weakness & other symptoms have been reported after stopping pms-fluoxetine. Symptoms usually disappear without treatment & can be alleviated by adjusting the dosage of pms-fluoxetine.
-Some newborns whose mothers took an SSRI or other newer antidepressants during pregnancy have shown symptoms like breathing & feeding difficulties, jitteriness & constant crying. - Isotretinoin (Oratane®, Apex Pharmacy) Warnings & Precautions:
-There have been increasing incidences of foetal malformation following topical administration of tretinoin.
-Use of topical tretinoin is not recommended during pregnancy, esp. in the 1st trimester.
-Care is required during treatment with isotretinoin as sudden onset of decreased night vision that may affect one's ability to drive or operate machinery at night has been reported.
Avoid waxing, dermatological abrasions, facial peels & some hair treatments while using Oratane capsules & for 6 months after isotretinoin treatment is stopped.
Interactions:
-Isotretinoin can reduce the effect of carbamazepine by increasing carbamazepine elimination. - Lactulose (Pms-lactulose®, IDS) Precautions:
-Additional laxatives should not be administered with lactulose solution.
-If diarrhoea occurs when using lactulose in Portal Systemic Encephalopathy (PSE), it may severely deplete fluids & potassium & may intensify symptoms of PSE hence potassium levels should be monitored during long-term treatment with lactulose.
-Caution needed if an unusual diarrheal condition occurs during lactulose therapy.
-Debilitated patients who receive lactulose for more than 6 months should have serum electrolytes (e.g. potassium, chloride, carbon dioxide) measured periodically during therapy.
Undesirable effects:
-During the first few days of therapy, lactulose frequently produces gaseous distention, belching, flatulence, borborygmi, &/or abdominal discomfort such as cramping. These usually subside with continued therapy but dosage reduction may be required.
-Diarrhoea indicates overdosage & responds to dosage reduction. Potential complications of diarrhoea include fluid loss, hypokalemia & hypernatremia.
-Infants receiving lactulose may develop dehydration & hyponatremia. - Methylphenidate HCl (Concerta®, Johnson & Johnson) Concerta® may cause dizziness, therefore patients are advised to exercise caution when driving, operating machinery, or engaging in other potentially hazardous activities.
New ADRs: Nervousness, disorientation, confusional state, alopecia, hypersensitivity reactions such as angioedema, anaphylactic reactions, auricular swelling, bullous conditions, exfoliative conditions, urticarias, pruritus, rashes, eruptions & exanthemas. - Nifedipine (Adalat®, Bayer) Special warnings:
-Careful monitoring of blood pressure must be exercised when administering nifedipine with IV magnesium sulfate due to possible excessive fall in blood pressure which could harm mother & fetus.
-Nifedipine is metabolised via CYP450 3A4 system hence drugs that are known to either inhibit or induce this enzyme system may therefore alter the first pass or clearance of nifedipine
-CYP450 3A4 inhibitors may lead to increased plasma concentrations of nifedipine; They include macrolide antibiotics (e.g., erythromycin), anti-HIV protease inhibitors (e.g., ritonavir), azole antimycotics (e.g., ketoconazole), antidepressants i.e. nefazodone & fluoxetine, quinupristin/dalfopristin, valproic acid, cimetidine. Upon co-administration with these drugs, blood pressure should be monitored & nifedipine dose may have to be reduced if necessary.
New ADRs: Allergic reaction, allergic oedema/ angioedema (including larynx oedema), anaphylactic/anaphylactoid reaction), anxiety reactions, sleep disorders, migraine, par-/dysaesthesia, nosebleed, gastrointestinal & abdominal pain, vomiting, joint swelling, polyuria, dysuria, erectile dysfunction, unspecific pain, chills.
Interactions:
-Upon co-administration with phenytoin, bioavailability of nifedipine is reduced & efficacy weakened hence dose adjustment of nifedipine should be considered when both drugs are concomitantly administered & when treatment with phenytoin is discontinued.
-A decrease in nifedipine plasma concentrations cannot be excluded when carbamazepine or phenobarbitone is concomitantly administered.
-Upon co-administration of tacrolimus & nifedipine, tacrolimus plasma concentrations should be monitored & dose reduced if necessary.
-Administration of nifedipine with grapefruit juice results in elevated plasma concentrations & prolonged action of nifedipine due to a decreased first pass metabolism or reduced clearance. Consequently blood pressure lowering effect may be increased hence ingestion of grapefruit/grapefruit juice is to be avoided.
Posology:
-Co-administration with CYP 3A4 inhibitors or CYP 3A4 inducers may result in the recommendation to adapt the nifedipine dose or not to use nifedipine at all.
-Grapefruit juice is to be avoided when administering nifedipine. - Olmesartan medoxomil (Olmetec®, Pfizer) Contraindications:
-Patients who become pregnant should discontinue the use of olmesartan medoxomil as soon as possible unless no alternative to a drug acting on the rennin-angiotensin system can be found.
Precautions:
-There is an increased risk of renal insufficiency when patients with bilateral renal artery stenosis (or stenosis of the artery to a single functioning kidney) are treated with medicinal products that affect the rennin-angiotensin system.
New ADRs: Vomiting, pruritus, acute renal failure, blood creatinine increased, hyperkalaemia.
|
October 2007
- Alendronate sodium (Fosamax®, MSD) Precautions:
-Discontinuation of biphosphonate therapy should be considered in patients with ONJ based on individual benefit/risk assessment.
-Dental surgery may exacerbate ONJ.
-Known risk factors for ONJ include co-morbid disorders like periodontal disease.
-For patients requiring invasive dental surgery (e.g., tooth extraction, dental implants), clinical judgment of the treating physician &/or oral surgeon should guide the management plan, including biphosphonate treatment of each patient based on individual benefit/risk assessment. - Beclomethasone Dipropionate (Clenil® pressurised inhalation solution, IDS) Special warnings on appropriate use of inhaler and adherence to a comprehensive asthma management plan have been added. Cautions on the possible systemic effects of inhaled corticosteroids, monitoring of growth of children taking corticosteroids, abrupt stopping of treatment and transiting from oral to inhaled corticosteroids due to adrenocortical suppression and possible unmasking of allergies. Special care is necessary in patients with active quiescent pulmonary TB.
Undesirable effects:
-Candidiasis of the mouth & throat (thrush) can occur especially at doses > 400 mcg beclometasone dipropionate/day. This is treatable with topical antifungals without discontinuing Clenil®.
-Paradoxical bronchospasm should be treated immediately with a rapid-acting inhaled bronchodilator & beclometasone dipropionate discontinued immediately.
New ADRs: Cushing's syndrome, Cushingoid features, adrenal suppression, growth retardation in children & adolescents, decrease in bone mineral density, cataract & glaucoma, throat irritation (use of volumatic spacer may help). - Cholestyramine (Pms-Cholestyramine®, IDS) Caution should be exercised when pms-Cholestyramine is administered to a nursing mother. Precautions:
-The current medications of the patient should be reviewed for their potential to increase serum LDL-C or total cholesterol.
-Cholestyramine potentially may cause steatorrhea or accentuate pre-existing steatorrhea & this may require reduction & adjustment of dosage.
Interactions:
-The concomitant drug, e.g. digitalis, should be re-titrated to avoid over-dosage when cholestyramine is discontinued.
-Pms-Cholestyramine may interfere with the pharmacokinetics of drugs (e.g. estrogens) that undergo enterohepatic recirculation.
-Although cholestyramine has been shown to reduce the bioavailability of HMG-CoA reductase inhibitors, the clinical cholesterol-lowering effects of an HMG-CoA reductase inhibitor & cholestyramine have been shown to be additive.
New ADRs: Dental bleeding, diuresis, weight loss/gain, increased libido, swollen glands, edema, dental caries. - Epoetin alfa (Eprex®, Johnson & Johnson) Special Warnings and Precautions:
-In all patients, haemoglobin (Hb) levels should be closely monitored due to a potential increased risk of thromboembolic events & fatal outcomes when patients are treated at Hb levels above the recommended target.
-Erythropoiesis-stimulating agents (ESAs) are not necessarily equivalent, therefore patients should only be switched from one ESA (such as EPREX) to another ESA with caution.
-In patients with chronic renal failure, maintenance Hb concentration should not exceed the upper limit of the target Hb concentration. Hb levels > 12g/dL may be associated with a higher risk of cardiovascular events, including death.
New ADRs: Increase in blood pressure, aggravation of existing hypertension, diarrhoea, nausea, pyrexia, vomiting, myalgia, hypertensive crisis with encephalopathy & seizures, shunt thromboses, porphyria. - Famotidine (Famodine, CCM Pharmaceuticals) Dosage adjustment is required for patients with moderate to severe renal insufficiency.
Since CNS effects have been reported in patients with moderate to severe renal insufficiency, to avoid excess accumulation of the drug dose of famotidine may be reduced to half the recommended dose.
Contraindications:
-Hypersensitivity to any component of the drug.
-Cross-sensitivity in this class of compounds has been observed, therefore Famodine should not be administered to patients with a history of hypersensitivity to other H2-receptor antagonists.Warnings & precautions:
-Dosage adjustments recommended in the elderly as this group of patients are more likely to have decreased renal function& it may be useful to monitor renal function.
-As CNS adverse effects have been reported in patients with moderate (CrCl < 50 ml/min) & severe (CrCl < 10 ml/min) renal insufficiency, famotidine dosage should be reduced in such patients.
Famotidine is detectable in human milk. Nursing mothers should avoid breast-feeding.
New ADRs: Liver enzymes abnormalities, cholestatic jaundice, anaphylaxis, depression, anxiety disorders, confusion, hallucinations, toxic epidermal necrolysis, A-V block(with iv H2-receptor antagonists). - Formoterol (Foradil®, Novartis) New warnings & precautions for use: In a study with salmeterol (a long-acting beta2-adrenergic agonist), a higher rate of death due to asthma was observed in patients treated with salmeterol compared with placebo. Dose of Foradil® should be individualized to the patient's needs & should be at the lowest possible dose to fulfil the therapeutic objective & not be increased beyond the maximum recommended dose.
Foradil® should not be used in conjunction with another long-acting beta2-agonist.
When treating asthmatic patients, Foradil® should only be used as additional therapy for patients not adequately controlled on other asthma-controller medications (e.g. low- to medium-dose inhaled corticosteroids) or whose disease severity clearly warrants initiation of treatment with two maintenance therapies, including Foradil®.
In patients not currently receiving anti-inflammatory therapy, this must be initiated at the same time as Foradil®.
Placebo-controlled clinical studies of at least 4 weeks treatment duration with Foradil® suggested a higher incidence of serious asthma exacerbations in patients who received Foradil® than in those who received placebo.
Foradil® must not be initiated or the dose increased during an asthma exacerbation.
Foradil® must not be used to relieve the acute symptoms of an asthma attack. In the event of an acute attack, a short-acting beta2-agonist should be used.
New ADRs: Dysgeusia, Oedema peripheral. - Gadoxetic acid, disodium (Primovist®, Zuellig) Special warnings:
-Reports of nephrogenic systemic fibrosis (NSF)/nephrogenic fibrosing dermopathy (NFD) associated with the use of some gadolinium-containing contrast agents in patients with severe renal impairment (GFR<30ml/min/1.73m2). Possibility that NSF/NFD may occur with Primovist®, hence only use Primovist in these patients if benefits outweigh the risks.
-No robust evidence that haemodialysis can prevent or treat the development of NSF but haemodialysis shortly after Primovist® administration in patients currently recently receiving haemodialysis may be useful at removing Primovist® from the body. No evidence to support the initiation of haemodialysis for prevention or treatment of NSF in patients not already undergoing haemodialysis. - Isradipine (Dynacirc® SRO, Novartis) Special warnings & precautions for use:
-Angina pectoris may occur, predominantly in patients with pre-existing coronary artery disease. In patients with pre-existing angina pectoris, frequency, duration & severity of anginal attacks may be increased by rapid dosage increments or at the start of treatment.Food interactions:
-Concomitant intake of grapefruit juice may increase the bioavailability of isradipine.New ADRs: Polyuria, malaise, weight increased, stroke, syncope, transient ischemic attack, lethargy, dry mouth, constipation, diarrhoea, insomnia, chest pain. - Measles, mumps & rubella virus vaccine live (M-M-R II, MSD) Dosage & administration:
-Local health authorities may recommend mumps vaccination in a mumps outbreak situation.New ADRs: Vasculitis, pneumonia, pruritis. - Medroxyprogesterone acetate (Depo-provera®, Pfizer) Additional Warnings & Precautions-Use of combined estrogen/progestin by postmenopausal women has been reported to increase the risk of breast cancer.
-Estrogens with or without progestins should not be used for the prevention of cardiovascular disease. Several randomized, prospective trials on the long-term effects (see Posology) of a combined estrogen/progestin regimen in postmenopausal women have reported an increased risk of cardiovascular events such as myocardial infarction, coronary heart disease, stroke & venous thromboembolism.
-Study has shown increased risk of developing probable dementia & mild cognitive impairment (MCI) in postmenopausal women 65 years of age or older hence use of HT to prevent dementia or MCI in women is not recommended.
-Study has shown that estrogen plus progestin increased the risk of ovarian cancer but this risk was not statistically significant.
-A complete medical & family history should be taken before the initiation of any hormone therapy. Pretreatment & periodic physical examinations should include blood pressure, breasts, abdomen & pelvic organs, including cervical cytology. - Montelukast sodium (Singulair®, MSD) New ADRs: Erythema nodosum, dizziness, tremor, depression, suicidal thinking & behaviour (suicidality).
- Pantoprazole (Controloc®, Hyphens Marketing) Special warnings & precautions for use:
-In the presence of any alarm symptom (e.g. significant unintentional weight loss, recurrent vomiting, dysphagia, haematemesis, anaemia or melaena) & when gastric ulcer is suspected or present, malignancy should be excluded, as treatment with pantoprazole may alleviate symptoms & delay diagnosis. Further investigation is to be considered if symptoms persist despite adequate treatment.
-In long-term treatment with controloc 20 mg tablets, esp. when exceeding a treatment period of 1 year, patients should be kept under regular surveillance.
-Pantoprazole, as all acid-blocking medicines, may reduce the absorption of vitamin B12 (cyanocobalamin) due to hypo- or achlorhydria, hence this should be considered in patients with reduced body stores or risk factors for reduced vitamin B12 absorption on long-term therapy.Pantoprazole interacts with coumarin anticoagulants, and atazanavir.
Contraindications:
-Pantoprazole, like other PPIs, should not be co-administered with atazanavir.
New ADRs: Vomiting, dry mouth, leukopenia, thrombocytopenia, arthralgia, hallucination, disorientation, confusion. - Pneumococcal 7-valent conjugate (Prevenar®, Wyeth) When Prevenar® is co-administered with hexavalent vaccines (DTaP/Hib(PRP-T)/IPV/HepB), the rate of febrile reactions was higher compared to that occurring following administration of hexavalent vaccines alone. Reactions were mostly moderate (< or = 39 degree celsius) & transient.
New ADR: Urticaria-like rash.
-An increased relative risk of hospitalization for various conditions (wheezing diagnoses) has been reported in infants receiving Prevenar® & could be due to concomitantly administered vaccines, changes in those vaccines, yearly variation in respiratory syncytial virus (RSV) or influenza infections, or secular trends in respiratory disease incidence. - Raloxifene HCl (Evista®, Eli Lilly) Special warnings & precautions for use:
-Study has shown that there was an increase in death due to stroke in women assigned to raloxifene, therefore caution when prescribing raloxifene for postmenopausal women with a history of stroke or other significant stroke factors, such as transient ischemic attack or atrial fibrillation.New ADRs:Thrombocytopenia, peripheral oedema, venous/arterial thromboembolic reaction. - Ritonavir (Norvir®, Abbott) Contraindications:
-Ritonavir may produce large increases in the plasma levels of alfuzosin hence alfuzosin should not be coadministered with ritonavir to avoid serious adverse events.Precautions:
-During the initial phase of combination antiretroviral therapy (including Norvir) when the immune system responds, HIV-infected patients may develop an inflammatory response to asymptomatic or residual opportunistic infections (such as Mycobacterium avium infection, cytomegalovirus, Pneumocystis carinii pneumonia or tuberculosis), which may necessitate further evaluation & treatment. - Sitagliptin phosphate (Januvia®, MSD) New ADRs: Anaphylaxis, angioedema, rash, urticaria.
- Sulfasalazine (PMS-Sulfasalazine, IDS) Contraindications:
-Intestinal & urinary obstructions.
-Sulfasalazine should not be used in patients in whom acute asthmatic attacks, urticaria, rhinitis or other allergic manifestations are precipitated by ASA or other NSAIDs as fatal anaphylactic reactions have occurred in such individuals.
Warnings:
-Use sulfasalazine only after critical appraisal of the risk to benefit in patients with hepatic or renal damage, blood dyscrasias, severe allergy or bronchial asthma. Pancreatitis has been observed in some susceptible individuals.
-Deaths associated with the use of sulfasalazine have been reported from hypersensitivity reactions, agranulocytosis, aplastic anemia, other blood dyscrasias, renal & liver damage, irreversible neuromuscular & CNS changes & fibrosing alveolitis. Presence of clinical signs like sore throat, fever, pallor, purpura or jaundice may be indications of serious blood disorders. Complete blood counts & urinalysis with careful microscopic examination should be done frequently in patients receiving sulfasalazine.
-Oligospermia with infertility have been observed in men treated with sulfasalazine.
Precautions:
-Patients allergic to furosemide, thiazide diuretics, sulfonylureas, carbonic anhydrous inhibitors or salicylates may also be allergic to sulfasalazine.
-Sulfasalazine can be toxic like other sulfonamides, esp. sulfapyridine, hence it should be administered under medical supervision & the usual precautions of sulfonamide therapy should be observed.
-Bone marrow depression (leukopenia) has been reported usually within the first 3 months of starting treatment & is usually reversible on stopping sulfasalazine. A full blood count, including differential white blood cell count, should be carried out before starting therapy & monitored closely during the first few months of treatment, thereafter patients should be screened if their condition changes or if they have symptoms of infection.
-Liver function tests & urinalysis should be carried out before & periodically during therapy in patients with renal deficiency or impaired hepatic function & in those with severe allergy or bronchial asthma.
-When concurrent therapy with other drugs is administered, as in rheumatoid arthritis, the recommended frequency of monitoring is every second week during the first three months & every six months thereafter.
-Adequate fluid intake must be maintained in order to prevent crystalluria & stone formation.
Interactions:
oral antibiotics, anticoagulants, coumarin- or indandione-derivative, anticonvulsants, hydantoin, antidiabetic agents.
bone marrow depressants, hemolytics, hepatotoxic medications, methotrexate, phenylbutazone, sulfinpyrazone, photosensitizing medications, Probenecid, MTX.
New ADRs: Reversible oligospermia, megaloblastic (macrocytic) anemia, cyanosis, pneumonitis, vasculitis, pleuritic, pericarditis with or without tamponade, allergic myocarditis, polyarteritis nodosa, L.E. syndrome, hepatitis, hepatic necrosis, arthralgia, bloody diarrhoea, impaired digoxin absorption, hearing loss, urine/skin discoloration, goiter production, diuresis, hypoglycemia.
Desensitization: Patients with rash, often associated with fever, can frequently be desensitized by treatment with graduated doses of sulfasalazine. Desensitization should not be attempted in patients with a history of agranulocytosis, or in those who have experienced an anaphylactic reaction with sulfasalazine previously. - Varicella virus vaccine live (Varivax®, MSD) For children 12 months to 12 years of age: If a second dose is administered, it should be given a minimum of 3 months later.
- Ziprasidone HCl (Zeldox®, Pfizer) New ADRs: Facial droop, tardive dyskinesia, dysphagia, swollen tongue, enuresis & urinary incontinence.
|
September 2007
- Adefovir dipivoxil (Hepsera®, GSK) Posology:
-Caution should be exercised when prescribing Hepsera® to the elderly, noting the greater frequency of decreased renal or cardiac function in these patients & the increase in concomitant diseases or use of other medicinal products concomitantly in the elderly.
Special warnings:
-Occurrence of lactic acidosis (in the absence of hypoxemia), sometimes fatal, usually associated with severe hepatomegaly & hepatic steatosis, have been reported with the use of nucleoside analogues.
-Treatment with nucleoside analogues should be discontinued when rapidly elevating aminotransferase levels, progressive hepatomegaly or metabolic lactic acidosis of unknown etiology occur.
-Caution should be exercised when prescribing nucleoside analogues to any patient (particularly obese women) with hepatomegaly, or other known risk factors for liver disease.
New ADR: Vomiting.
-Mild to moderate increases in serum creatinine concentrations, hypophosphatemia & a decrease in carnitine concentrations were reported. - Cefuroxime axetil (Zinnat®, GSK) Interactions: In common with other antibiotics, Zinnat® may affect the gut flora, leading to lower oestrogen reabsorption & reduced efficacy of combined oral contraceptives.
As Zinnat® may cause dizziness, patients should be warned to be cautious when driving or operating machinery.
New ADRs: Overgrowth of Candida, dizziness, abdominal pain. - Chloral hydrate (pms-Chloral hydrate syrup, IDS) Contraindicated in the following:
-Severe cardiac disease due to possibly cardiac arrhythmias & hypotension associated with larger doses.
-Esophagitis or gastric or duodenal ulcer due to irritant properties.
Warnings:
-Psychological dependence possible under long-term use of larger than usual dose, therefore exercise caution when administering drug to mentally depressed or suicidal patients.
-Sudden withdrawal may result in hallucinations & symptoms similar to delirium tremens (sometimes fatal), therefore chloral hydrate should be tapered gradually.
-Paediatric patients should be monitored for CNS & respiratory depressive effects. Deaths associated with the use of chloral hydrate for sedation prior to diagnostic or therapeutic procedures have been reported. Caution in calculating & administering the proper dose. Sedation in children with adenoidal hypertrophy & obstructive sleep apnoea (OSA) has been reported to cause life-threatening respiratory obstruction. Children with OSA from other causes may be at risk too. Laryngeal edema resulting in severe respiratory difficulty in a child has been reported.
Precautions:
-In children, gastric irritation & vomiting may occur following administration of chloral hydrate syrup hence it should be well diluted.
-Due to prolonged half-lives of chloral hydrate's metabolites, excessive CNS depression in children may occur due to accumulation following repeated dosing hence degree of sedation should be monitored & caregivers cautioned against exceeding prescribed dosage.
-Neonates should be monitored for increased bilirubin concentrations as hyperbilirubinemia may occur due to the competition of chloral hydrate metabolites with bilirubin for hepatic glucuronidation.
-In elderly patients likely to have age-related hepatic/renal function impairment & in debilitated patients or patients prone to CNS depression, reduction of dose may be needed to avoid oversedation or other adverse effects.
-Careful monitoring is required in patients with respiratory insufficiency.
Chloral Hydrate interacts with other CNS depressants like alcohol, barbiturates & tranquilizers, alcohol.
New ADRs: Hangover effect, hypotension, ventricular/atrial arrhythmias, torsades de pointes, depression of myocardial contractility, shortening of refractory periods, life-threatening respiratory obstruction episodes (in young children), acute intermittent porphyria, ketonuria (rare), ptosis, allergic conjunctivitis, keratoconjunctivitis, increase in middle ear pressure (in infants & children). - Ciclosporine (Gengraf®, Abbott) Warnings: Those receiving cyclosporine (also other immunosuppressants) are at an increased risk for development of lymphomas & other malignancies, particularly of the skin. Increased risk appears related to the intensity & duration of immunosuppression rather than to the use of specific agents.
Because of the danger of oversuppression of the immune system resulting in increased risk of infection or malignancy, a treatment regimen containing multiple immunosuppressants should be used with caution. There have been reports of convulsions in adults & pediatric patients receiving cyclosporine, particularly in combination with high doses methylprednisolone.
Encephalopathy has been described post-market. Manifestations include impaired consciousness, convulsions, visual disturbances (including blindness), loss of motor function, movement disorders, psychiatric disturbances & changes in the white matter, all reversible upon discontinuation of cyclosporine. Predisposing factors include hypertension, hypomagnesemia, hypocholesterolaemia, high-dose corticosteroids, high cyclosporine blood concentrations, & graft-vs-host disease. Patients receiving liver transplant appear more susceptible to encephalopathy than those receiving kidney transplant.
A rare manifestation of cyclosporine-induced neurotoxicity, occurring in transplant patients more frequently than in other indications, is optic disc edema including papilloedema, with possible visual impairment, secondary to benign intracranial hypertension.
Care should also be taken in using cyclosporine with nephrotoxic drugs. - Clomipramine HCl (Anafranil® SR, Novartis) New ADR: Neuroleptic malignant syndrome.
- Estramustine (Estracyt®, Pfizer) Special warnings:
-Patients with prostate cancer & osteoblastic metastases are at risk for hypocalcemia & should have calcium levels closely monitored. - Melphalan (Alkeran®, GSK) New ADR: Anaemia.
New ADRs reported with injection, following isolated limb perfusion: Muscle atrophy, muscle fibrosis, myalgia, blood creatine phosphokinase increased, compartment syndrome, muscle necrosis, rhabdomyolysis. - Ranitidine HCl (Hyzan®, Apex Pharmacy) Precautions:
-Ranitidine dosage should be adjusted in patients with impaired renal function.
-Regular supervision of patients who are on NSAIDs concomitantly with ranitidine is recommended, esp. in the elderly & in those with a history of peptic ulcer.
-Rare clinical reports suggest that ranitidine may precipitate acute porphyric attacks, therefore ranitidine should be avoided in patients with a history of acute porphyria.New ADRs: Marrow hypoplasia, marrow aplasia, bradycardia, A-V block, vasculitis, blurred vision, changes in LFTs, hepatitis with or without jaundice, acute pancreatitis, mental confusion, depression, hallucinations, involuntary movement disorders, erythema multiforme, alopecia, bronchospasm, hypotension, anaphylactic shock, chest pain, impotence, breast symptoms in men.
|
