Sibutramine ( Meridia/Reductil ) is a noradrenaline and serotonin reuptake inhibitor indicated for weight loss. It has been available in Australia since January 2002 but is not funded by the PBS ( Pharmaceutical Benefit Scheme ).

To date, ADRAC ( Adverse Drug Reactions Advisory Committee ) has received 138 reports ( 404 adverse reactions ) associated with the use of Sibutramine.

The common adverse reactions reported are consistent with the product information and are listed as follows: nervous system 62 ( headache 20, dizziness 14, serotonin syndrome 5 ), psychiatric 50 ( depression 12, anxiety 11, insomnia 10, aggression 6, agitation 6 ), gastrointestinal 33 ( nausea 9, constipation 6, dry mouth 6 ), cardiac 31 ( rhythm disorders 11, palpitations 9, chest pain 4 ), vascular 26 ( hypertension 8 ), respiratory 15 ( dyspnoea 11 ).

Psychiatric reactions have been reported at both extremes of the spectrum, specifically depression and mania. Sibutramine was the sole suspected medicine in 11 of the 12 cases of depression. The time to onset was relatively short, ranging from 1 to 13 days. Most patients ( 11 ) recovered after stopping Sibutramine. The 12 reports included 2 of suicidal ideation and 2 of suicide Sibutramine was the sole suspected medicine in 2 of the 3 reports of mania. Both of these patients recovered after ceasing Sibutramine. The other manic event occurred in a patient with a history of previously well controlled bipolar disorder.

Reported cardiovascular adverse reactions have included cardiac rhythm disorders, palpitations and chest pain. Sibutramine was the sole suspected medicine in 27 cases. The two most serious adverse reactions were ventricular fibrillation with cardiac arrest and myocardial infarction. There have also been 8 reports of hypertension.

Serotonin syndrome was reported in 5 cases, with time to onset ranging from 1 to 22 days. Sibutramine was used with Tramadol in 2 cases, with Sertraline in 1 case and was the sole medication in the other 2 cases.

Sibutramine should not be used in combination with other CNS-active drugs, such as MAOIs and SSRIs, due to a possible interaction and the risk of serotonin syndrome. Sibutramine is not recommended for use in patients with a history of heart disease as it tends to increase heart rate and blood pressure.

Source: Australian Adverse Drug Reactions Bulletin, 2006


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