|LETTER TO THE EDITOR
|Year : 2012 | Volume
| Issue : 1 | Page : 142
Gairik Sengupta, Subhrojyoti Bhowmick, Avijit Hazra, Ananya Datta, Musfikur Rahaman
Department of Pharmacology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, India
|Date of Web Publication||14-Jan-2012|
Department of Pharmacology, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sengupta G, Bhowmick S, Hazra A, Datta A, Rahaman M. Authors' reply. Indian J Pharmacol 2012;44:142
We thank the authors' for their several pertinent observations on our article.
As rightfully observed, a more exhaustive table linking individual drugs to their suspected ADRs would have been more informative. However, the summary tables presented should suffice for the majority of the casual readers. Similarly, reorganizing the ADR listing by system organ class would have been interesting, but the number of ADRs were few to make this categorization worthwhile. The majority of ADRs were detected as symptoms complained by the patient. Some were signs (e.g. tremor, extrapyramidal reactions, and weight gain) and a few laboratory test abnormalities have also been reported.
The major indications have been mentioned - bipolar affective disorder, schizophrenia, and depression. Other common indications were obsessive compulsive disorder, other anxiety disorders, conversion disorders, and dementias. We excluded substance abuse disorders by protocol, since drug history could be unreliable from such subjects. We want to make it clear that, this being an observational study, the investigators had no role in the selection of drugs for the primary (mental) complaints or the co-morbid conditions. We kept a record of medication use for co-morbidities, rather than details of these co-morbidities.
Since many patients were receiving multiple psychotropic drugs, in some instances, it is possible that more than one drug would have contributed to a single ADR like tremor. However, the investigators have tried to the best of their ability, and in consultation with an experienced psychiatrist, to narrow down to the most likely drug, particular on the basis of temporal relationships and drug withdrawals in case of more than mild ADRs. We also relied on clinical assistance to distinguish disease related symptoms from suspected ADRs (e.g. insomnia and increased nightmares).
Possibly, donepezil induced painless blistering rash was the only unique ADR in our series for which we found no previous reference.
Drug withdrawals were done by the psychiatry consultants concerned in the event of ADRs that significantly inconvenienced the patient (e.g. constipation) or corrective medication was introduced (e.g. trihexiphenidyl for tremor). Unfortunately, we did not keep a record of the full details of the corrective medication used or other management offered and the long-term outcome.
Our study was observational - we did active surveillance for ADRs, looking for exposure and outcome at the same time. However, we did not have a control group as in epidemiological studies. Therefore, indices like relative risks and odds ratios were not calculated. We summarized by percentages and confidence intervals. This is also the reason why we cannot claim that the study yields true incidence and prevalence figures - it offers only an idea. We have stated as such in the concluding paragraph.
Regarding the adverse events listed by us, we can offer no definite explanation on why weight gain far outnumbered increased appetite. However, the latter is a subjective report while we relied on our own measurement to decide upon weight gain (at least 5 kg more than known weight before starting incriminated drug). Two of the three subjects with increased appetite also showed weight gain. We were not in a position to order computed tomography (CT) or magnetic resonance imaging (MRI), and seizure precipitation was inferred from clinical history. The drug incriminated for hypothyroidism (both cases) was lithium, while those for alopecia were valproic acid, lithium, and selective serotonin reuptake inhibitor antidepressants. We could have made an attempt to calculate mean (or median) onset time of ADRs, but this would be inappropriate for two reasons - in many cases onset time was only approximate (in weeks rather than days) and the ADRs were quite different, so that an overall mean (or median) onset time would not be very meaningful. We did not follow-up the cases and therefore have no data from which mean (or median) resolution time could be calculated.