Induced hypertension

Magnesium plays an important role in the transmission of nerve impulses. It is also important in the activity of many enzyme reactions, for example carbohydrate metabolism. Magnesium sulfate is used as replacement therapy in hypomagnesemia Magnesium sulfate (MgS04) is used in die prevention and control of seizures in obstetric patients with pregnancy-induced hypertension (PIH, also referred to as eclampsia and preeclampsia). It may also be added to TPN mixtures. 

Anand et al. 1987). The authors hypothesized that the ocular effects associated with endosulfan may be a result of prolonged hypertension (although no data on blood pressure were presented, and there is no other information to indicate that chronically administered endosulfan induces hypertension) or an endosulfan-induced vitamin A deficiency (which was observed in this study). Although the rabbit may represent a uniquely sensitive species, the possibility that long-term exposure of persons at hazardous waste sites to endosulfan may result in adverse effects on ocular tissues cannot be eliminated. 

Based upon this rationale, the effect of pharmacologically induced hypertension on clinical and imaging outcomes is being investigated in patients with acute stroke. 

In one study, patients with significant diffusion-perfusion mismatch on MRI, large vessel occlusive disease, and fluctuating neurological deficits were found to be more likely to respond. Induced hypertension correlated with improved cortical cerebral... 

Hayashi S, Nehls DG, Kieck CF, Vielma J, DeGirolami U, Crowell RM. Beneficial effects of induced hypertension on experimental stroke in awake monkeys. J Neuro surg 1984 60 151-157. 

Cole DJ, Matsumura JS, Drummond JC, Schell RM. Focal cerebral ischemia in rats effects of induced hypertension, during reperfusion, on cbf. J Cereb Blood Flow Metab 1992 12 64-69. 

Rordorf G, Koroshetz WJ, Ezzeddine MA, Segal AZ, Buonanno FS. A pilot study of drug-induced hypertension for treatment of acute stroke. Neurology 2001 56(9) 1210-1213. 

Koenig MA, Geocadin RG, de Grouchy M, Glasgow J, Vimal S, Restrepo L, Wityk RJ. Safety of induced hypertension therapy in patients with acute ischemic stroke. Neurocrit Care 2006 4(l) 3-7. 

Walker BR, Edwards CRW. Licorice-induced hypertension and syndromes of apparent miner-... 

The possible mechanism kidney-induced hypertension is discussed in Section 2.4.2, Mechanisms of Toxicity. Lead appears to affect vitamin D metabolism in renal tubule cells, such that circulating levels of the vitamin D hormone, 1,25-dihydroxyvitamin D, are reduced. This effect is discussed later in this section under Other Systemic Effects. 

Ding Y, Vaziri ND, Gonick HC. 1998. Lead-induced hypertension ii. response to sequential infusions of 1- arginine, superoxide dismutase, and nitroprusside. Environmental Research 76/2 107-113. 

Johanson BB, Isaksson O. Circadial variation of cerebral vessel vulnerability during adrenaline induced hypertension. In Cerebral Blood Flow Effect of Nerves and Neurotransmitters (Heistad DD, Marais ML, Eds.), 1st Edn. Amsterdam Elsevier Biomedical 1982, 367-375. 

Baseline hypokalemia may suggest mineralocorticoid-induced hypertension. The presence of protein, blood cells, and casts in the urine may indicate renovascular disease. 

Patients should be closely monitored for side effects that require aggressive intervention such as irinotecan-induced diarrhea and bevacizumab-induced GI perforation. Patients should be evaluated for other treatment-specific side effects such as oxaliplatin-induced neuropathy, cetuximab and panitumumab-induced skin rash, and bevacizumab-induced hypertension and proteinuria. 

Makaritsis KP, Handy DE, Johns C, Kobilka BK, Gavras I, Gavras H (1999) Role of the a2B-adrenergic receptor in the development of salt-induced hypertension. Hypertension 33 14-17... 

More and more babies are being born prematurely (elective Caesarian sections for pregnancy-induced hypertension, diabetes, foetal distress of varying kinds). Neonatal units need highly specialized skills in managing these tiny creatures - occasionally as much as 10-12 weeks premature. Among the very many special problems of the premature baby are those related to drug administration and elimination. 

Due to the frequent unwanted effects and, in case of tranylcypromine, the numerous and dangerous interactions MAO-inhibitors are more and more replaced by the much less problematic SSRIs. Compounds belonging to this group are citalopram, escitalopram, fluoxetine, paroxetine and sertraline. They are used clinically in the therapy of depression, bulimia and obsessive-compulsive disorders. All SSRIs show a slow onset of action (1-2 weeks). They may induce insomnia and weight loss. The antidepressant ven-lafaxine inhibits both, serotonin and noradrenaline re-uptake and might therefore additionally induce hypertension. 

The injection of a vasoconstrictor, which causes an increase in mean arterial blood pressure, results in activation of the baroreceptors and increased neural input to the cardiovascular centers in the medulla oblongata. The reflex compensation for the drug-induced hypertension includes an increase in parasympathetic nerve activity and a decrease in sympathetic nerve activity. This combined alteration in neural firing reduces cardiac rate and force and the tone of vascular smooth muscle. As a consequence of the altered neural control of both the heart and the blood vessels, the rise in blood pressure induced by the drug is opposed and blunted. 

The MAOIs are as effective as the heterocyclic antidepressants and the newer agents, such as the SSRIs. However, at least two forms of life-threatening toxicity (hepatotoxicity and dietary tyramine-induced hypertensive crisis ) have been associated with their chronic use. For this reason, the MAOIs are not considered first-line agents in the treatment of depression. They are generally reserved for treatment of depressions that resist therapeutic trials of the newer, safer antidepressants. However, a new transdermal formulation of selegiline undergoing clinical trials demonstrates antidepressant efficacy without concerns of liver toxicity or dietary tyramine-induced hypertension. 

Chronotropic effect positive. Glycerin/ ethanol extract of the leaf and seed oil, administered intragastrically to desoxycorti-costerone acetate-induced hypertensive rats at doses of 500 and 125 mg/kg, respectively, was active " . 

OE216 Khayyal, M. T., M. A. el-Ghazaly, D. M. Abdallah, N. N. Nassar, S. N. Okpanyi, and M. H. Kreuter. Blood pressure lowering effect of an olive leaf extract (Olea europaea) in L-NAME induced hypertension in rats. Arzneimittelforschung 2002 52(11) 797-802. 

Unlabeled Uses Treatment of pralidoxime-induced hypertension, arrhythmias, asthma, bladder instability, cardiac diseases, diabetes mellitus, erectile dysfunction, extravasation (dopamine and epinephrine), hyperhidrosis, myocardial infarction, Raynaud s phenomenon, surgery, sympathetic pain... 

Self-medication of a MAOI-induced hypertensive crisis is controversial. In a hypertensive crisis the lack of access to medical services may lead to even greater complications. A small dose of medication taken as part of a larger plan to blunt the rise in blood pressure may prevent serious complications. However, headache is common, has multiple causes, and patients may not accurately identify a headache due to hypertension without a blood pressure check. In addition, selfadministration of nifedipine, especially sublingually, may result in needless and perhaps dangerous drops in blood pressure. 

B. M. Altura and B. T. Altura, Role of magnesium and calcium in alcohol-induced hypertension and strokes as probed by in-vivo television microscopy, digital image microscopy, optical spectroscopy, P-NMR spectroscopy and a unique magnesium ion-selective electrode. Alcohol. Clin. Exp. Res., 1994,18,1057-1068. 

Unfortunately, even perfect compliance with dietary and other restrictions does not guarantee complete protection from MAOI-induced hypertensive crises. There are reports of spontaneous hypertension associated with MAOI therapy. Most of these involved the use of tranylcypromine, but phenelzine also has been implicated. 

If a patient s blood pressure is greatly increased, pharmacological treatment should be instituted. Treatments for MAOI-induced hypertension include administration of the calcium channel blocker nifedipine and use of drugs with a-adrenergic-blocking properties, such as phentolamine (5 mg intravenous). Because treatment with phentolamine may be associated with cardiac arrhythmias or severe hypotension, this approach should be carried out only in an emergency department setting. 

Metaraminol has a longer duration of action than some other vasopressors and care should be taken to avoid inducing hypertension. The dose is 0.5-5 mg as a slow intravenous bolus. If necessary, 15-100 mg may be diluted in normal saline (500 ml) and given by infusion. The dose of methoxamine is 2-5 mg intravenously. 

The human reproductive process does not fit perfectly into the animal model of reproductive and developmental toxicity. Conditions of the fetal-maternal unit that affect both mother and child have not been adequately addressed in this monograph, although there is some evidence that some of these adverse outcomes, such as pregnancy-induced hypertension, may be related to environmental exposure (Tabacova et al., 1998 Dawson et al., 1999). This is a promising frontier for new research. We have also not dealt with genetic susceptibility to developmental toxicants. Advances in this field may illuminate many of the mysteries of how toxicants act, and on whom. Limited data are available on mechanisms of action (see section 5.2.4). The work on oxidative stress in pregnancy (Tabacova et al., 1998 Hubei,... 

No more than 7 mg can be taken within 48 hours. It is a possible teratogen and produces a number of side effects such as Gl upset, peripheral neuritis, rashes, blood dyscrasias (bleeding, bruising, tiredness), lowers body temperature, induces hypertension, and so on. However, its effects on inflammation and swelling are dramatic and it can be extremely effective when given as a prophylactic and for beginning, acute attacks. 

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