Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020538 (hypertension)
 170,190 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Propranolol is a commonly used drug; of new and refilled prescriptions, it ranked no. 1 in 1984 and no. 2 in 1985. Medical conditions for its use include angina pectoris, myocardial infarction, hypertension, cardiac dysrhythmias, hypertrophic subaortic stenosis, migraine headache, hyperthyroidism, and pheochromocytoma. Almost all dental practitioners will treat a patient receiving propranolol for one of these conditions. The following recommendations seem appropriate at this time: The patient should continue to receive propranolol during dental treatment. Sudden withdrawal of the beta-blocker will cost the patient the benefit of propranolol therapy and may lead to acute myocardial ischemia. Acute stress should be minimized, as hypertensive responses may also be caused by endogenously released epinephrine. Short appointments scheduled in the morning, possibly with conscious sedation, should be considered. The dosage of adrenergic vasoconstrictors should be limited and gingival retraction cord containing epinephrine avoided entirely. The blood pressure should be taken approximately 5 minutes after local anesthesia is administered to determine if a systemic response has occurred. In the unlikely event of a hypertensive emergency, a rapidly acting, short-duration antihypertensive drug, such as the alpha-blocker phentolamine (Regitine, 5 mg intravenously) should be administered. Sublingual nitroglycerin (Nitrostat, 0.4 mg) may be useful as a nonparenteral alternative. These recommendations apply to other nonselective beta-blockers, including nadolol (Corgard) and timolol (Blocadren). They may also apply to labetalol (Normodyne, Trandate), a nonselective beta-antagonist with some alpha-blocking activity and to pindolol (Visken), a beta-blocker with some intrinsic beta 2-agonistic activity.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Hypertensive response to levonordefrin in a patient receiving propranolol: report of case. 327 28

Labetalol (Trandate; Allen & Hanburys), a combined alpha- and beta-adrenergic blocking agent, was compared with the more commonly used peripheral vasodilator, dihydrallazine (Nepresol; Ciba), each administered as an infusion, in the treatment of severe hypertension in 20 primigravidas at greater than or equal to 32 weeks' gestation. With the dosage regimen used in this study there was a tendency towards more effective blood pressure control with dihydrallazine. The pulse rate was unaffected by labetalol therapy and there were no harmful effects on the neonate or fetus directly attributable to either drug.
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PMID:Comparison of labetalol and dihydralazine in hypertensive emergencies of pregnancy. 355 Nov 27

Serial blood samples were obtained throughout pregnancy from 11 women with essential hypertension (EHT). Seven were treated with labetalol (Trandate) and 4 with alpha -methyl dopa (Aldomet). Nine patients were well-controlled throughout pregnancy. Their mean plasma renin concentrations (PRC) followed the profile determined in 18 normal patients studied serially. They remained in the upper normal range until the last month, when both treatment groups showed a fall in PRC. Mean plasma aldosterone (ALD) also followed a normal profile until late gestation when it too showed a sharp fall. Of the two patients who developed superimposed PIH, one, who received labetalol, developed severe hypertension at 35 weeks, requiring delivery. Although PRC increased early in this pregnancy, ALD did not, remaining low throughout. Serum potassium [K+] measurements were also very low in this patient. The second patient only became hypertensive at 40 weeks and had PRC and ALD profiles resembling those in the successfully treated EHTs. There was a strong positive correlation throughout between serum potassium and ALD measurements (p less than 0.001) but none between PRC and ALD. This latter agrees with the known lack of correlation between PRC and ALD in normal pregnancy and may suggest that changes in electrolyte balance are more important stimuli to ALD secretion during pregnancy.
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PMID:Renin and aldosterone concentrations in pregnant essential hypertensives - a prospective study. 634 44

Labetalol (Trandate) is a new antihypertensive agent with both alpha- and beta-adrenoceptor blocking properties. In a double-blind cross-over study the antihypertensive action and side-effects of labetalol and propranolol were compared in 18 previously untreated outpatients with hypertension, WHO stage I--III. Mean daily dose of labetalol was 667 mg and of propranolol 129 mg. Labetalol reduced systolic and diastolic blood pressure in the seated and upright position significantly more than propranolol. The pulse rate reduction was greater with propranolol. Side-effects were more pronounced with propranolol. The antihypertensive effect, effect on pulse rate and pharmacokinetics of a single oral dose of 400 mg labetalol were studied in 6 patients with normal and 6 patients with impaired renal function (creatinine clearance less than 20 ml/min), all belonging to WHO stage I--II. A significant fall in pulse rate and systolic and diastolic blood pressure was observed in both groups, the duration being more than 25 h. No difference was found between the two groups. From the serum concentration-time curves the elimination rate constant, elimination half-life and area under the curve were calculated. The mean values of the two groups did not differ significantly. A pronounced interindividual variation was found in both groups.
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PMID:Labetalol in the treatment of hypertension in patients with normal and impaired renal function. 696 60

1 Eighty-five women with severe hypertension complicating pregnancy were treated with oral labetalol (Trandate). Six of these had a twin pregnancy and 54 had proteinuria. 2 Effective control of the blood pressure was achieved in all but six patients. The maximum dose of labetalol prescribed was 1200 mg daily. There were no significant maternal or foetal side-effects. 3 Foeto-placental function was carefully monitored in all patients. Twenty-four of the 89 infants born alive showed evidence of intra-uterine growth retardation, the highest incidence occurring in the group of patients with essential hypertension complicated by pregnancy induced hypertension. 4 The low perinatal mortality of 4.4% was a reflection of the meticulous control of the blood pressure. 5 There were no congenital malformations or evidence of oculotoxicity in any of the infants delivered. 6 The efficient hypotensive action of orally administered labetalol together with the absence of maternal and foetal side effects and consequent improved perinatal mortality confirms that it is an eminently suitable drug for the treatment of hypertension complicating pregnancy.
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PMID:The evaluation of labetalol in the treatment of hypertension complicating pregnancy. 709 96

During pregnancy, the maternal, placental and fetal physiological characteristics constantly evolve and thereby constantly alter drug bioavailability in the mother and feto-placental unit. Gastric emptying time is increased and bowel movements are reduced. Distribution in the maternal body is mainly influenced by body mass variations, water content and fat stores. Metabolic capacity of the liver appears unchanged but renal clearance of drugs is gradually increased. The placental transfer of most drugs mainly consists of passive diffusion between the maternal and fetal circulations, along their respective concentration gradients. Only the free, unbound and non-ionized fraction of the drug readily crosses the membranes. Four anti-hypertensive drugs have been granted a license for the treatment of PE since the year 2000: these are Clonidine (Catapressan), Nicardipine (Loxen+), Labetalol (Trandate), Dihydralazine (Nepressol). Dihydralazine, Labetalol and Nicardipine are not contraindicated in the breast feeding mother. The administration of a long acting Benzodiazepine during pregnancy can lead to new born intoxication of variable severity and duration. These symptoms may precede a withdrawal syndrome (hyper-excitability, tremor, gastro-intestinal upset, such as diarrhea or vomiting). Breast feeding by mothers using benzodiazepines (Nitrazepam and Midazolam) is not recommended. In France, the use of low molecular weight heparins is not recommended during pregnancy whereas in the United States, they are recommended as a prophylactic measure. Their high molecular weight prevents their diffusion across the placental membrane and therefore prevents any fetal or neonatal risk. Bromocriptine is used as an inhibitor of lactation. During the post-partum period, serious accidents have been described: these consist of systemic hypertension, fits, infarcts (cardiac and neurological). It is contraindicated in case of systemic hypertension.
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PMID:[Drugs during preeclampsia. Fetal risks and pharmacology]. 2034 63