Hypertension antidepressants

Patients receiving monoamine oxidase inhibitors (MAOI) as antidepressant therapy have been especially subject to the hypertensive effects of vasoactive amines (52). These dietary amines have also been impHcated as causative agents ia migraine. Other aaturaHy occurring alkaloids (qv) have been recognized for centuries as possessing neurological stimulant and depressant properties. 

The amphetamines and the anorexiants should not be given during or within 14 days after administration of monoamine oxidase inhibitors (see Chap. 31) because the patient may experience hypertensive crisis and intracranial hemorrhage. When guanethidine is administered with the amphetamines or the anorexiants, the antihypertensive effect of guanethidine may decrease. Coadministration of the amphetamines or the anorexiants with the tricyclic antidepressants may decrease the effects of the amphetamines or the anorexiants. 

The MAOI antidepressant drag s are contraindicated in patients widi known hypersensitivity to die drug s, liver and kidney disease, cerebrovascular disease, hypertension, or congestive heart failure and in die elderly. These drag s are given cautiously to patients witii impaired liver function, history of seizures, parkinsonian symptoms, diabetes, or hyperthyroidism. 

MAO Is The MAOIs are less frequently prescribed than other antidepressants, probably because of the risk of hypertensive crisis when food containing tyramine is ingested during M AOI therapy. Fhtients receiving MAOIs... 

The antidiarrheal drugs cause an additive CNS depression when administered with alcohol, antihistamines, narcotics, and sedatives or hypnotics. There are additive cholinergic effects when administered with other drugp having anticholinergic activity, such as antidepressants or antihistamines. Concurrent use of the antidiarrheals witii a monoamine oxidase inhibitor increases the risk of a hypertensive crisis. 

Serious adverse effects of epinephrine potentially occur when it is given in an excessive dose, or too rapidly, for example, as an intravenous bolus or a rapid intravenous infusion. These include ventricular dysrhythmias, angina, myocardial infarction, pulmonary edema, sudden sharp increase in blood pressure, and cerebral hemorrhage. The risk of epinephrine adverse effects is also potentially increased in patients with hypertension or ischemic heart disease, and in those using (3-blockers (due to unopposed epinephrine action on vascular Ui-adrenergic receptors), monoamine oxidase inhibitors, tricyclic antidepressants, or cocaine. Even in these patients, there is no absolute contraindication for the use of epinephrine in the treatment of anaphylaxis [1,5,6]. 

A number of non-hormonal therapies have been studied for symptomatic management of vasomotor symptoms, including antidepressants [e.g., selective serotonin reuptake inhibitors (SSRIs) and venlafaxine], herbal products (e.g., soy, black cohosh, and dong quai), and a group of miscellaneous agents (e.g., gabapentin, clonidine, and megestrol). The choice of therapy depends on the patient s concomitant disease states, such as depression and hypertension, and the risk for potential adverse effects. 

Drugs that block the catecholamine uptake process (e.g., cocaine, tricyclic antidepressants, and phenothiazines) are apt to block the anti hypertensive action of which of the following drugs ... 

Increased or decreased antidepressant response increased toxicity Decreased antihypertensive efficacy Decreased antihypertensive efficacy Increased hypoglycemic effects Possible additive lowering of seizure threshold Decreased antihypertensive efficacy tachycardia CNS stimulation Increased therapeutic and possibly toxic effects of both drugs hypertensive crisis delirium seizures hyperpyrexia serotonin syndrome Increased hypoglycemic effects... 

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. 

Tricyclic antidepressants are cardiotoxic, inducing tachycardias and an increased tendency for ventricular arrhythmias with high doses. This dose dependent cardiotoxicity gives these agents a low therapeutic index. Overdoses are characterized by cardiac conduction disturbances, hyperpyrexia, hypertension, confusion, hallucinations, seizures and coma and there is a high mortality rate in suicide attempts. Depressed patients should therefore not be given more than one week supply of these drugs. 

Tricyclic antidepressants are notorious for their risk to be involved in drug-drug interactions. Additive anticholinergic effects can be expected in combination with antihistamines, antipsychotics and anticholinergic-type anti-Parkinson agents. Hepatic enzyme-inducing agents increase their hepatic metabolism while enzyme inhibitors may potentiate the effects of tricyclics. Concomitant use with monoamine oxidase inhibitors will produce hypertension, hyperpyrexia and convulsions. 

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. 

Can antidepressants such as tricyclics or buproprion augment the effect of stimulants on nondepressed children with ADHD Randomized controlled trials have yet to address this question. Nonetheless, such combinations are common in clinical practice. One case report showed leukopenia in a child treated with a combination of MPH and tricyclics for 4 months, although the doses were not specified (Burke et ah, 1995). Another case report indicated that obsessive-compulsive symptoms developed secondary to the combination of MPH and tricyclics (Pataki et ah, 1993). On a cautionary note, MPH has been found to interact with guanethidine to produce paradoxical hypotension. Patients on monoamine oxidose (MAO) inhibitors are likely to develop hypertensive crises if given a stimulant. 

Coadministration of beta-blockers can potentiate rebound hypertension upon discontinuation of medications, and it is therefore recommended that the beta-blocker be withdrawn before the tt2 agonist (Physicians Desk Reference, 2001). Tricyclic antidepressants may also produce changes in sinus node and AV conduction, and it is recommended that they be used cautiously in combination with tt2 agonists (Physicians Desk Reference, 2001). However, in child psychiatric practice, there has been debate about whether there are adverse interactions related to concomitant use of tricyclics and tt2 agonists. Finally, the tt2 agonists may potentiate the effects of CNS depressants (e.g., barbiturates) or other medications that produce sedation, so lower doses of each may be warranted. 

The following side effects apply to the irreversible, nonselective MAOI antidepressants (phenelzine and tranylcypromine). The most common side effects are orthostatic hypotension, headache, insomnia, weight gain, sexual dysfunction, peripheral edema, and afternoon somnolence. Although MAOIs do not have significant affinity for muscarinic receptors, anticholinergic-like side effects are present at the beginning of treatment. Dry mouth is common but not as marked as in TCA therapy. Fortunately, the more serious side effects, such as hypertensive crisis and serotonin syndrome, are not common. 

Methylphenidate may decrease therapeutic effects of concomitantly administered antihypertensive medications and may potentiate effects of warfarin, phenytoin, phenylbutazone, and tricyclic antidepressants. When methylphenidate and MAOIs are coadministered, hypertensive crisis may result. 

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