VOLUME 25 : NUMBER 5 : October 2002
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Some of the views expressed in the following notes on newly approved products should be regarded as preliminary, as there may have been limited published data at the time of publication, and little experience in Australia of their safety or efficacy. However, the Editorial Executive Committee believes that comments made in good faith at an early stage may still be of value. Before new drugs are prescribed, the Committee believes it is important that more detailed information is obtained from the manufacturer's approved product information, a drug information centre or some other appropriate source.
100 mg, 200 mg and 400 mg film-coated tablets
Approved indication: schizophrenia
Australian Medicines Handbook section 18.2
Amisulpride is a benzamide antipsychotic which antagonises dopamine receptors. It binds to the D2 and D3 dopamine receptors, but has little affinity for muscarinic or serotonin receptors. This pattern of activity differs from that seen with atypical antipsychotics.
The oral formulation has a bioavailability of 48%, but is not
extensively metabolised. Most of the drug is excreted unchanged,
with an elimination half-life of 12 hours. Clearance is reduced in
patients with renal impairment.
A meta-analysis of trials which compared amisulpride with
conventional antipsychotic drugs found that it had greater efficacy
in patients with acute schizophrenia.1 Amisulpride has been
compared with haloperidol in patients with chronic schizophrenia.
After one year, a study of 60 in-patients found no significant
difference in overall efficacy, but there was a trend suggesting
amisulpride may be more beneficial for negative
Another larger study (488 patients) also found that amisulpride had
a greater effect than haloperidol on negative symptoms.3
Like the atypical antipsychotics, amisulpride causes fewer extra
pyramidal adverse effects than conventional drugs. Its extra
pyramidal effects are dose related. Common adverse effects include
insomnia, anxiety, agitation and weight gain. The release of
prolactin may result in problems such as galactorrhoea and
amenorrhoea. There is a potential for amisulpride to cause torsade
de pointes as it prolongs the QT interval. Amisulpride is therefore
contraindicated in combination with other drugs which cause QT
prolongation. Caution is also advised if the patient is taking
diuretics or other drugs which may cause hypokalaemia.
While amisulpride has effects which are similar to those of the
atypical antipsychotics, there is little information about the
relative benefits. One eight-week study found amisulpride and
risperidone had similar efficacy in acute schizophrenia.4
1. Leucht S, Pitschel-Walz G,
Engel RR, Kissling W. Amisulpride, an unusual 'atypical'
antipsychotic: a meta-analysis of randomized controlled trials. Am
J Psychiatry 2002;159:188-90.
2. Speller JC, Barnes TR, Curson DA, Pantelis C, Alberts JL. One year, low-dose neuroleptic study of in-patients with chronic schizophrenia characterised by persistent negative symptoms. Br J Psychiatry 1997;171:564-8.
3. Colonna L, Saleem P, Dondey-Nouvel L, Rein W. Long-term safety and efficacy of amisulpride in subchronic or chronic schizophrenia. Int Clin Pychopharmacol 2000;15:13-22.
4. Peuskens J, Bech P, Möller HJ, Bale R, Fleurot O, Rein W. Amisulpride vs. risperidone in the treatment of acute exacerbations of schizophrenia. Psychiatry Res 1999;88:107-17.
First published online October 2002