Why we must fight concept of carer as killer
Further to Professor Pirmohamed's excellent and informative article on adverse drug reactions (Clinical, October 18) it may be of interest that to observe an ADR with an incidence of one in 100, the medicine must be tested in an average of 300 patients.
For an ADR with an incidence of one in 1,000, some 6,000 patients must be followed.
Given that it is likely to require the assessment of several incidences of an ADR to determine a causal relationship between a drug and the ADR, the importance of post-marketing surveillance via, for example, the yellow card scheme, becomes apparent.
Dr Jim Laughton
Head of Medical Affairs