Concentration-effect relationships for oxprenolol in patients with essential hypertension

CNS-related performance and haemodynamics of metoprolol-Oros and propranolol after single and 3 days dosing in healthy volunteers

1. The effects of metoprolol-Oros 14/190 once daily, propranolol 80 mg twice daily and temazepam 10 mg once daily on central nervous system (CNS) related performance and haemodynamic variables were evaluated in a double-blind, randomized, placebo controlled, crossover study in 12 healthy volunteers. Drugs were administered for 3 consecutive days except for temazepam, which was administered on days 1 and 3 only. Treatment effects were evaluated at 0, 2, 5 and 8 h on days 1 and 3. 2. Neither beta-adrenoceptor blocker had significant effects in a battery of tests after single or 3 days dosing. Temazepam caused a decrease in saccadic peak velocity of 37.4 degrees s-1 (95% CI: 6.0, 68.9) at 2 h and an increase of auditory reaction times of 11.5 ms (0.2, 22.8) at 8 h on day 1. No significant effects of temazepam were detected on day 3. 3. Both beta-adrenoceptor blockers reduced exercise heart rate. Peak effects were measured at 2 h 40 min after propranolol but not metoprolol-Oros (difference, day 1:20 (11, 29) beats min-1, day 3:13 (8, 19) beats min-1). Both beta-adrenoceptor blockers significantly reduced baseline exercise heart rate on day 3. Compared with day 1, metoprolol-Oros caused larger reductions of exercise heart rate at all times on day 3. 4. Metoprolol-Oros and propranolol caused similar reductions of systolic- and diastolic blood pressure on days 1 and 3. Temazepam caused a small reduction in diastolic blood pressure at 5 h 40 min on day 1 but was otherwise devoid of haemodynamic effects.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of exercise on the pharmacokinetics of drugs

Since many patients with a wide variety of diseases are nowadays stimulated to adopt a physically active lifestyle, the question of the influence of exercise on the pharmacokinetics of drugs has become more and more relevant. Because exercise influences a large number of physiological factors that also determine the pharmacokinetics of drugs, including haemodynamics, metabolism, pH, temperature and gastrointestinal function, it can be expected to have an effect on the pharmacokinetic parameters (absorption, distribution, elimination) of certain agents. However, only a very limited number of studies has been directed towards this issue, and only a very few drugs have been studied. Nevertheless, it is clear that exercise does influence the pharmacokinetics of certain drugs, although the magnitude and direction of the effects vary. This is not surprising in view of the widely differing physicochemical properties of drugs, the many possible--often opposing--effects of exercise on the parameters affecting drug pharmacokinetics and the different types of exercise performed. The chance of a clinically relevant effect of exercise on the pharmacokinetics of a particular drug is largest in those with a steep dose-response curve, a narrow therapeutic range, a need for continuity of therapeutic effectiveness and a relatively short half-life, in combination with intensive exercise of long duration. If untoward drug effects occur during or after exercise, a change in the pharmacokinetics of the drug related to the exercise should be seriously considered as a possible cause.