Madam, – The tragic events in Bray last August that resulted in the death of two young men have raised vitally important questions about the possible side-effects of antidepressants, and about the knowledge that informs the licensing of medicines in Ireland. The answers to these questions offered by Kate Holmquist in her recent column (October 10th), and endorsed in a Letter to the Editor by a number of psychiatrists (October 19th), are wrong in at least three respects.
First, it is untrue to say there is no scientific evidence of links between anti-depressants and homicidal behaviour, and between anti-depressants and actual suicides. In an article published in September 2006 in the leading open-access medical journal PLoS Medicine, David Healy, Andrew Herxheimer and David Menkes conclude that “clinical trial and pharmacovigilance data point to possible links between these drugs and violent behaviours”. They argued that while existing evidence suggests serious violence associated with antidepressant use is very rare, it requires urgent examination.
Evidence from clinical trials has led to regulatory authorities in some jurisdictions warning doctors about the risk of suicide to patients taking these medicines, and also the risk of violent harm to others.
Second, the dismissal of “anecdotal claims” about serious side-effects of antidepressants is contrary to recent moves to recognise and value patients’ experiential knowledge of medicines. Rather than trivialising patients’ experiences of medicines, there have been repeated calls to value this “consumer intelligence” and “popular epidemiology” and to find ways of including it in drug safety research.
In a study published in the International Journal of Risk Safety in Medicine in 2002, a team of researchers led by Charles Medawar judged the collective weight of the patients’ direct accounts to be profound as they uncovered previously unrecognised patterns of experiences coinciding with dosage increases and withdrawal of therapy.
Third, the claim that the Irish Medicines Board (the IMB) and other regulatory authorities do not rely on information produced by the pharmaceutical industry is incorrect. Decision-making about the licensing of medicines is based on pre-marketing clinical trials, and these trials are largely sponsored by the pharmaceutical industry. Pharmacovigilance is seriously hampered by the under-reporting of adverse drug reactions (ADRs) by doctors. In 2007, the IMB received only 206 ADR reports from GPs, indicating that fewer than one in 10 GPs on average submit one ADR report a year to this voluntary reporting system.
Finally, in respect of Holmquist’s reassurances about the IMB’s independence, the funding of this agency needs to be considered. The 2007 report of the Oireachtas Committee on the Adverse Side-Effects of Pharmaceuticals noted that the existing funding arrangement whereby the IMB relies on fees paid by pharmaceutical companies “tends to put the drug companies in the position of clients of the IMB with the inference that the IMB has a corresponding obligation to meet its ‘clients’ needs”. – Yours, etc,