Concept explainers
Nifedipine is an antihypertension medication that is also used to reduce the workload on the heart. The study below compares the effects of two different types of capsules used to administer the drug to patients (GITS—red line, and Cotracten X—blue line). Each graph shows changes with time following initial administra- tion of the capsules. Figure A compares the levels of nifedipine in the blood with each capsule type. The ability of the different cap- sules to reduce workload on the heart by altering blood pressure or heart rate is shown in Figures B and C, respectively.
Which type of capsule would you expect to have fewer side effects?
Source: M. J. Brown and C. B. Toal. 2008. Formulation of long-acting nifedipine tablets influences the heart rate and sympathetic nervous system response in hypertensive patients. British Journal of Clinical Pharmacology 65:646–652.
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Chapter 44 Solutions
Biology: The Dynamic Science (MindTap Course List)
- Nifedipine is an antihypertension medication that is also used to reduce the workload on the heart. The study below compares the effects of two different types of capsules used to administer the drug to patients (GITSred line, and Cotracten Xblue line). Each graph shows changes with time following initial administra- tion of the capsules. Figure A compares the levels of nifedipine in the blood with each capsule type. The ability of the different cap- sules to reduce workload on the heart by altering blood pressure or heart rate is shown in Figures B and C, respectively. Are elevated plasma levels of nifedipine(above 10 ng/mL) required for the drug to perform its actions? Source: M. J. Brown and C. B. Toal. 2008. Formulation of long-acting nifedipine tablets influences the heart rate and sympathetic nervous system response in hypertensive patients. British Journal of Clinical Pharmacology 65:646652.arrow_forwardThe circulatory system is controlled in the Medulla oblongata through the accelerator and inhibitory centres. Draw a schematic diagram to show the sequences of events following low or high blood pressure detected at the baroreceptors.arrow_forwardA Physician orders 40 mL of an IV solution containing ampicillin to run in 30 minutes with a microdrop infusion set. This is to be followed by 500 mL of NS to infuse at 50 drops per minute with an infusion set of 20 gtt/mL. What is the total infusion time for the two IV solutions?arrow_forward
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- A patient taking ketoconazole, an antifungal agent, was also prescribed dofetilide to treat arrhythmias. The therapeutic window for dofetilide is 8–15 μg/mL. The patient’s serum levels are taken 48 hours after his first dose and his serum levels are 3 μg/mL. What is the cause of these reduced serum levels?arrow_forward1) Explain the principle of the electrical impedance cell counting. 2) State 3 Haematology analyzer and their manufacturers. 3) CV for automated instrument is +/- 1% to +/- 2% compared to manual count with CV +/- 10%. Can you explain their differences?arrow_forwardWomersley number (a) of a human aorta is 20 and for the rabbit aorta is 17, the blood density is approximately the same across the species. The values of viscosity were 0.0035 Ns/m² for the human and 0.0040 Ns/m² for the rabbit. The diameter of the aorta is 2.0 cm for the man, and 0.7 cm for the rabbit, estimate the heart rate beats per minute (bpm) for both species.arrow_forward
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