In recent months, the Pharmacovigilance Branch, HSA has received three reports of adverse drug reactions (ADR) associated with 2 slimming health products. On further investigation, the products namely, ‘Relacore' and ‘Lami', were found to contain sibutramine, an undeclared western drug ingredient used as an appetite suppressant in the management of obesity.

In June 2008, HSA issued a press statement to alert the public of the adulterated product labelled as ‘Relacore'. This was prompted by two ADR reports involving two adult patients (a male and female) in their early 20s, that were brought to HSA's attention by doctors at a hospital. Noteworthy was that both patients admitted to purchasing the slimming product over the Internet. One of the patient provided samples of ‘Relacore', which was ordered from a Chinese website. The product was subsequently tested by HSA's analytical laboratory to contain 12.22 mg of sibutramine in each capsule.

 

The adulterated product labelled as ‘Relacore' (could be a counterfeit of the product sold in the US) was promoted as a dietary supplement and claimed to contain “stress mitigating compound” for “belly fat and stress control”. (Refer to photo of the product).

The male patient mentioned above, presented with symptoms of psychosis, including hallucination and palpitation at the emergency department. On further probing by the doctor, he admitted to taking ‘Relacore' for 3 months at a dose of 3-4 capsules daily, which was beyond the dose of 2 capsules recommended on the product's label. Based on the amount of sibutramine found in each capsule, the patient had unwittingly consumed 36-48 mg of sibutramine daily (maximum daily dose of subitramine is 15 mg). This could explain the adverse reactions observed in the patient, taking into consideration the close temporal relationship between the onset of adverse reaction and date of ingestion of the adulterated product.

Case report

A 29 year-old female presented to a general practitioner's clinic with symptoms of palpitation, breathlessness, auditory hallucination and labile mood after taking a traditional Jamu supplement labelled as ‘Lami'. The patient has been taking ‘Lami' since 2007. Adverse symptoms manifested when she took eight capsules of the product, which was four times above the dose of two capsules/ day recommended on the label. The patient provided the sample, which was also tested by HSA to contain sibutramine.

Sibutramine is a noradrenaline and serotonin reuptake inhibitor indicated for weight loss. The commonly reported adverse reactions include insomnia, headache and anxiety. Tachycardia and hypertension have also been reported in some patients.

 

Sibutramine is also known to exhibit significant dopamine reuptake inhibition and some authors have postulated that this could possibly lead to the development of psychotic symptoms, especially in the event of an overdose.¹ This is based on the postulation that the dopamine reuptake inhibition could result in excess dopamine in the synaptic clefts and a consequent increased dopaminergic neurotransmission, in line with the dopamine hypothesis of

psychosis.^{2, 3}

Given the increasing trend of consumers turning to the Internet for purchase of health products, healthcare professionals are encouraged to ask patients about the consumption of such complementary medicines or health supplements. Very often, patients may not regard these products as medicines and not mention about it to their doctors. The information may be important to physicians in making a differential diagnosis of the adverse events experienced by patients.