The influence of tocolytic drugs on cardiac function, large arteries, and resistance vessels.

PURPOSE: Beta-2 adrenoceptor agonistic drugs like ritodrine have been the reference tocolytic drugs, but are associated with cardiovascular side-effects. Atosiban, a newer drug, is a competitive antagonist of oxytocin and has been claimed to have fewer cardiovascular side effects. Until now, there has mainly been a subjective reporting of adverse reactions and few objective cardiovascular data. Evaluation of the acute effects of therapeutic doses of ritodrine and atosiban compared with placebo on cardiac function, large artery properties, blood pressure, and resistance vessels. METHODS: A double-blind, randomized trial was carried out in 20 non-pregnant female volunteers. Hemodynamic measurements were made under standardized conditions during kinetic steady state. Cardiac output was measured with echocardiography, large artery properties with an echo-tracking device. The effect on the microcirculation was estimated using the total peripheral resistance index (TPRI). RESULTS: Atosiban did not differ from placebo. With ritodrine, cardiac function increased by 79% compared with placebo because of a rise in heart rate (91%). TPRI decreased by 48%. Ritodrine increased the distensibility of the common carotid artery by 62% and the compliance by 83%, independent of blood pressure. Compliance of the common femoral artery increased independently of pressure by 33% and the distensibility by 59%. Aortic pulse wave velocity was not influenced by either medication. CONCLUSIONS: The present study shows potential beneficial vascular effects of ritodrine that are counterbalanced by the cardiac effects. Atosiban has no clinically relevant cardiovascular effects and may be a good alternative for ritodrine in pregnant women at risk of cardiovascular complications.

Prices of antihypertensive medicines in sub-Saharan Africa and alignment to WHO's model list of essential medicines.

OBJECTIVE: To investigate compliance of National Essential Medicines Lists (NEMLs) with the WHO Essential Medicines List (WHO/EML) in 2007 and to compare prices of antihypertensive drugs in and between 13 sub-Saharan African countries. METHODOLOGY: Data on NEMLs and drug prices were collected from 65 public and 65 private pharmacies (five of each per country). Prices were compared with the International Drug Price Indicator Guide (IDPIG). The cost of drug treatment within a country was calculated using defined daily doses (DDD) and between countries using DDD prices adjusted for purchasing power parity-based gross domestic product per capita. RESULTS: All surveyed countries had a NEML. However, none of these lists were in complete alignment with the 2007 WHO/EML, and 38% had not been updated in the last 5 years. Surveyed medicines were cheaper when on the NEMLs; they were also cheaper in public than in private pharmacies. Prices varied greatly per medicine. A large majority of the public prices were higher than those indicated by the IDPIG. Overall, hydrochlorothiazide is the cheapest drug. CONCLUSION: There are substantial differences in NEML composition between the 13 countries. The proportion of NEMLs not regularly updated was double the global United Nations estimates. Prices of WHO/EML-advised drugs differ greatly between drugs and for each drug within and between countries. In general, the use of drugs on the NEML improves financial accessibility, and these drugs should be prescribed preferentially.