Under-reporting adverse drug reactions

Reporting of suspicions of dependence should be to the national adverse drug reaction centre, but other reporting requirements under national laws must be followed. 

The relation between neuroleptic drug therapy and myocarditis and cardiomyopathy has been examined using the international database on adverse drug reactions run by the World Health Organization (152). Myocarditis and cardiomyopathy were reported rarely as suspected adverse drug reactions, and accounted for under 0.1% (n = 2121) of almost 2.5 million reports. The association of clozapine with those adverse reactions was statistically significant (231 reports out of 24 730), as was the association with other antipsychotics (89 of 60 775). 

Primary reports describing adverse reactions and drug-induced diseases include spontaneous reports and other unpublished data available from the manufacturer or the FDA. All reports of adverse reactions reported to the FDA can be retrieved (without identifiers) under the legal authority of the Freedom of Information Act. Anecdotal and descriptive reports of ADRs (including case reports and case series) are occasionally reported in the literature but are often incomplete and inconclusive. Guidelines for evaluating adverse drug reaction reports have been described (56). 

Wherever possible, emphasis in this Encyclopedia has been placed on information that has come from systematic reviews and clinical trials of all kinds this is reflected in new headings under which trial results are reported (observational studies, randomized studies, placebo-controUed studies). However, because many reports of adverse drug reactions (about 30%) are anecdotal, with evidence from one or just a few cases, many individual case studies (see below) have also been included. We need better methods to make use of the information that this large body of anecdotes provides. 

In cases when the medicinal product has been registered in other countries, it is desirable to present information on the adverse drug reaction reports collected during the post-registration survey of the medicinal product. If possible, these data shall be discussed in respect to the data for consumption of the medicinal product. It is necessary to attach the publications made on the safety of the medicinal product under registration and the safety of other medicinal products containing the same active substance(s). 

Lumley CE, Walker SR, Hall GC, Staunton N, Grob PR. The under-reporting of adverse drug reactions seen in general practice. Pharm Med 1986 1 205-12. 

With all that has been said about our genomic and pharmacogenomic differences, it is probably no surprise that adverse drug reactions to marketed drugs are one of the 10 leading causes of death in the United States—the direct cost of harm alone is 75 to 130 billion in the United States. Under-reported they may be, but the FDA already receives 250,000 to 500,000 reports of... 

All suspected adverse drug reactions occurring as a result of treatment under this patient group direction must be reported to a senior medical practitioner responsible for the area in which the PGD is used and the patient s general practitioner... 

Hazell, L., Shakir, S. A. (2006). Under-reporting of adverse drug reactions A systematic review. Drug Safety An InternationalJournal of Medical Toxicology and Drug Experience, 29(5), 385—396. 

In a further 10 placebo-controlled trials including 492 patients on Hypericum and 455 patients on placebo, a total of 31 suspected adverse drug reactions were seen in 27 patients treated with Hypericum extract and 49 suspected adverse drug reactions were documented for 34 patients who took placebo [234, 235, 239, 240, 242, 249, 250, 251, 252]. Gastrointestinal symptoms were reported most frequently with 12 cases under Hypericum treatment and 10 cases in placebo groups. Other symptoms such as tiredness (Hypericum 2 cases, placebo 1 case), sleep disturbances (2 cases under either treatment) were very rare. 

Few drugs are more controversial. More adverse reactions to the drug have been reported to the FDA than any other drug in the 24-year history of the FDA s adverse drug reaction reporting system. Thomas G. Whitde and Richard Wieland (The Story Behind Prozac. the Killer Drug) write, Based on documents recently obtained by under the Freedom of Information Act, as of September 16,1993,28,623 reports of adverse reactions to Prozac had been received by the FDA. ... 

Alvarez-Requejo, A. et al.. Under-reporting of adverse drug reactions. Estimate based on a spontaneous reporting scheme and a sentinel system. Eur J Clin Pharmacol, 54(6) 483-488,1998. 

In the United States, adverse reaction reporting for veterinary pharmaceuticals is conducted under a programme operated by the Center for Veterinary Medicine (CVM), which is part of the US Food and Drug Administration (FDA). The FDA provides cumulative veterinary adverse drug experience reports (currently 1987 to 30 April 2012) on its website (http //www.fda.gov/ AnimalVeterinary/default.htm). These reports cover adverse drug reaction... 

P. G. M. van der Heijden, E. P. van Puijenbroek, S. van Buuren and J. W. van deer Hofstede, On the assessment of adverse drug reactions from spontaneous reporting systems the influence of under-reporting on odds ratios, Stat. Med., 2002, 21, 2027-2044. 

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