Antihistamines Antihypertensives

Psychotropic effect is a side effect, with undesired action Analgesics Narcotics Antihistamines Antihypertensives Appetite suppressants ... 

Long-acting antihistamine Antihypertensive Cardiovascular Antidepressant Veterinary drug... 

While drug interactions based on pharmacokinetics do occur with sedative-hypnotics, the most common drug interaction is additive CNS depression. Additive effects can be predicted with concomitant use of alcoholic beverages, anticonvulsants, opioid analgesics and phenothiazines. Less obvious but equally important is enhanced CNS depression with many antihistamines, antihypertensives, and antidepressants of the tricyclic class. The answer is (A). 

The hypotensive effects of most antihypertensive dru are increased when administered with diuretics and other antihypertensives. Many dnigp can interact with the antihypertensive drugs and decrease their effectiveness (eg, antidepressants, monoamine oxidase inhibitors, antihistamines, and sympathomimetic bronchodilators). When the ACE inhibitors are administered with the NSAIDs, their antihypertensive effect may be decreased. Absorption of the ACE inhibitors may be decreased when administered with the antacids. Administration of potassium-sparing diuretics or potassium supplements concurrently with the ACE inhibitors may cause hyperkalemia. When the angiotensin II receptor agonists are administered with... 

Other important pyrimidinone derivatives include temelastine 1123, an antihistaminic agent, urapidil 1124, an antihypertensive, and 5-hydroxymethyl-6-methyluracil (pentoxyl) 1125 which is used as a leukopoietic stimulant in wound healing. 

Quetiapine is metabolized by hepatic CYP 3A3/4. Concurrent administration of cytochrome P450-inducing drugs, such as carbamazepine, decreases blood levels of quetiapine. In such circumstances, increased doses of quetiapine are appropriate. Quetiapine does not appreciably affect the pharmacokinetics of other medications. Pharmacodynamic effects are expected if quetiapine is combined with medications that also have antihistaminic or a-adrenergic side effects. Because of its potential for inducing hypotension, quetiapine also may enhance the effects of certain antihypertensive agents. 

Other medications, which will not be discussed in the following chapters, have psychotropic actions that are considered to be side effects or adverse effects. Thus, some antihistamines (Le. products used to counteract allergic reactions) induce fatigue and drowsiness, and the same applies to some myorelaxants. Older antihypertensives (Le. agents reducing blood pressure) such as alpha-methyldopa (Aldomet ) or clonidine (Catapres 1) can cause fatigue and depression. 

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