Blood pressure drugs used

Equally important as their ability to lower blood pressure when used alone is the potentiation of all other antihypertensive drugs(7). The most commonly accepted explanation for this... 

Alpha-2-selective drugs are used primarily in the treatment of hypertension and spasticity. When treating hypertension, these drugs stimulate alpha-2 receptors located in the brain and brainstem. When stimulated, these central alpha-2 receptors exert an inhibitory effect on sympathetic discharge from the vasomotor center in the brainstem.34 Diminished sympathetic discharge results in a decrease in blood pressure. The use of alpha-2 agonists in lowering blood pressure is discussed in more detail in Chapter 21. 

SAFETY PROFILE A human poison by ingestion. Poison experimentally by intravenous, subcutaneous, and intraperitoneal routes. Moderately toxic by an unspecified route. Human systemic effects by ingestion sleep, increased pulse rate without blood pressure decrease, and chronic pulmonary edema or congestion, convulsions, headache, and blood pressure elevation. Used in production of drugs of abuse. When heated to decomposition it emits toxic fumes of NOx. 

In typieal physiological conditions wherein the plasma volume gets diminished sharply, as in hypovolemic shock, the immediate replaeement tends to restore the blood pressure. The use of plasma-extenders in sueh eonditions to restore the blood pressure are not regarded as the true vasopressor drugs for obvious reasons as they fail to affeet vasoeonstriction. 

McMahon C, Mitchell AZ, Klein JL et al (2010) Evaluation of blood pressure measurement using a miniature blood pressure transmitter with jacketed external telemetry in Cynomolgus monkeys. J Pharmacol Toxicol Methods 62 127-135 Misra A, Ganesh S, Shah SP (2003) Drug delivery to the central nervous system a review. J Pharm Pharm Sci 6 252-273... 

Physiological responses to prostaglandins encompass a variety of effects Some prostaglandins relax bronchial muscle others contract it Some stimulate uterine con tractions and have been used to induce therapeutic abortions PGEj dilates blood vessels and lowers blood pressure it inhibits the aggregation of platelets and offers promise as a drug to reduce the formation of blood clots... 

Epinephrine itself does find some use in clinical medicine. The drug is used in order to increase blood pressure in cases of circulatory collapse, and to relax the bronchial muscle in acute asthma and in anaphylactic reactions. These activities follow directly from the agent s physiologic role. The biogenetic precursor of epinephrine, norepinephrine, has activity in its own right as a mediator of sympathetic nerve action. (An apocryphal story has it that the term nor is derived from a label seen on a bottle of a key primary amine in a laboratory in Germany N ohne... 

Alkylamines have a variety of applications in the chemical industry as starting materials for the preparation of insecticides and pharmaceuticals. Labetalol, for instance, a so-called /3-blocker used for the treatment of hi h blood pressure, is prepared by SN2 reaction of an epoxide with a primary amine. The substance marketed for drug use is a mixture of all four possible stereoisomers, but the biological activity derives primarily from the (R,R) isomer. 

Ca2+ is an important intracellular second messenger that controls cellular functions including muscle contraction in smooth and cardiac muscle. Ca2+ channel blockers inhibit depolarization-induced Ca2+ entry into muscle cells in the cardiovascular system causing a decrease in blood pressure, decreased cardiac contractility, and antiarrhythmic effects. Therefore, these drugs are used clinically to treat hypertension, myocardial ischemia, and cardiac arrhythmias. 

Hypotension is defined as abnormally low blood pressure. In most cases, hypotension is adequately treated with general measures (e.g. physical exercise), dtug treatment is rarely required. Drugs used for the treatment of hypotension include a-adrenoceptor agonists and compounds which activate both a and (3 adrenoceptors. 

To evaluate die patient s response to tiierapy, and depending on die drug administered, die nurse may check die patient s blood pressure every hour, inquire whether pain has been relieved, or monitor die pulse every 15 minutes. After evaluation, certain otiier decisions may need to be made and plans of action implemented. For example, die nurse may need to notify die primary health care provider of a marked change in a patient s pulse and respiratory rate after a drug was administered, or die nurse may need to change die bed linen because sweating occurred after a drug used to lower die patient s elevated temperature was administered. 

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