Transdermal nitroglycerin in angina pectoris

Stress is sometimes involved in cardiac patients when a number of different drugs are necessary for treatment that are taken in a variety of dose regimes. Any new method for drug delivery that can relieve some of this stress is therefore of interest. Such a preparation is glyceryl trinitrate (GTN) in the form of a skin patch (Transiderm‐Nitro) and this was compared to placebo in a double‐blind cross‐over trial. Following a one‐week control period, patients were randomly allocated to three weeks treatment with placebo followed by three weeks with Transiderm‐Nitro (1–15 mg in 24 h) or vice versa. Analysis was performed on 77 cases, 37 in the placebo first group (group A) and 40 in the Transiderm‐Nitro first group (group B). Irrespective of treatment order, mean weekly anginal attack rates and GTN requirements were significantly less on the active patch than on placebo. Thus, there was a 21 per cent reduction in anginal attacks on placebo but 53 per cent reduction on Transiderm‐Nitro (p<O.OOl); while the mean GTN requirement was reduced by 29 per cent on placebo but 56 per cent on Transiderm‐Nitro (p<O.OOl). There were no significant changes in pulse rate or recumbent or upright blood pressure. Patients' preferences (blind) were in favour of Transiderm‐Nitro (p<O.OOl). The most frequent side‐effect was headache, which occurred in 22 per cent of patient; on Transiderm‐Nitro but in only 3 per cent on placebo (p<O.Ol). Skin rashes occurred in 5 per cent on Transiderm‐Nitro and 4 per cent on placebo (NS). This short‐term trial demonstrated highly significant effects from the transdermal GTN preparation in comparison to placebo.