Pharmaco-economic analysis of psychotropic drugs

To analyse cost and adverse reactions of psychotropic drugs for their cost-effective use.

Four hundred and sixty nine psychotropic formulations from CIMS, June 1998 were evaluated for (a) extent of variation in retail price for same strength and dosage form, (b) role of number of companies manufacturing the same formulation and (c) companies pricing their product at price less than average of maximum and minimum price in relation to number of products marketed by them. The side effects of antipsychotic and antidepressant drugs were graded for their severity and cumulative side effects score. Side effect index and cost index were calculated on relative basis and their product was used as cost benefit index.

Fifty per cent of psychotropic drugs had less than 100% price variation with highest of 2049% for risperidone 4 mg tablets. A direct relationship existed between the drug cost and price variation wherever the variation crossed 200%. Similar trend was noticed between the minimum price variations and the number of companies marketing the product. There was no appreciable relationship between number of products marketed and pricing by the manufacturer. Cumulative side effect score was lowest (10) for trifluoperazine and pimozide and highest (15) for risperidone amongst antipsychotic drugs, whereas amongst antidepressants fluoxetine had lowest (1.75) and amitryptyline had highest (28.5) cumulative side effect score.

One has to be more careful while selecting a brand of a drug when price variation is more (200-2049%). Trifluoperazine (1.0) and fluoxetine (1.7) were found to be most economical with better cost benefit index compared to thioridazine (494.2) and clomipramine (113.0) in their respective groups. Thus our analysis provides basic information regarding cost effective therapy with psychotropic drugs.