Abstract

Drugs which have been prescribed or have been taken on the patient’s own initiative may interfere with chemical estimations performed on body fluids. This possibility should be considered when tests are requested and when unexpected results are obtained. Similarly, other diagnostic tests may be affected, such as the ECG by digoxin and the EEG by psychotropic drugs. The widespread use of contraceptive pills must be kept in mind, as oestrogen-containing preparations affect the results of many chemical tests performed on the serum of healthy women (Table 1).