Phenothiazines Monoamine oxidase inhibitors

The most frequent side effect for diazepam is somnolence dizziness, ataxia, headache, nervousness, euphoria, and rash occur iess frequently. Excessive use of rectai diazepam may produce rebound seizures (63). Intravenous administration may produce infrequent respiratory depression and hypotension. Other sedative drugs, such as barbiturates, valproate, narcotics, phenothiazines, monoamine oxidase inhibitors, and antidepressants, can potentiate the effects of diazepam. 

Tricyclic antidepressants Monoamine oxidase inhibitors Selective serotonin reuptake inhibitors Antipsychotics Phenothiazines Risperidone Lithium... 

Beta-blockers interact with a large number of other medications. The combination of beta-blockers with calcium antagonists should be avoided, given the risk for hypotension and cardiac arrhythmias. Cimetidine, hydralazine, and alcohol all increase blood levels of beta-blockers, whereas rifampicin decreases their concentrations. Beta-blockers may increase blood levels of phenothiazines and other neuroleptics, clonidine, phen-ytoin, anesthetics, lidocaine, epinephrine, monoamine oxidase inhibitors and other antidepressants, benzodiazepines, and thyroxine. Beta-blockers decrease the effects of insulin and oral hypoglycemic agents. Smoking, oral contraceptives, carbamazepine, and nonsteroidal anti-inflammatory analgesics decrease the effects of beta-blockers (Coffey, 1990). 

Rare, familial hyperthermia (41 °C) associated with inhalation anaesthetics, muscle relaxants, tricyclic antidepressants, phenothiazine neuroleptics (particularly chlorpromazine) monoamine oxidase inhibitors and haloperidol. 

Drug interactions The depressant actions of morphine are enhanced by phenothiazines (see p. 127), monoamine oxidase inhibitors (see p.123), and tricyclic antidepressants (see p. 119 and Figure 14.5). Low doses of amphetamine (see p. 103) strangely enhance analgesia. Hydroxyzine (see p. 422) also enhances analgesia. 

Flurotyl should not be used in combination with drugs that lower the seizure threshold, such as monoamine oxidase inhibitors and phenothiazines. 

Imipramine, a substance with a structure similar to the phenothiazines (Figure 5) but varying in that the ring is a dibenzazepine rather than a phenothiazine, was the first active antidepressant of the nonmomoamine oxidase inhibitor series of agents. It, like the monoamine oxidase inhibitors, is effective in less than half the patients treated. Its mode of action is not clearly understood, but there is increasing evidence that it too exerts an effect on catechol amine metabolism (19). Although serious toxic effects have been uncommon, excitement, jaundice, and blood dyscrasias have occurred (17). 

Certain of the drugs used in the treatment of mental illness affected the caeruloplasmin-catalysed oxidation of NA and 5-HT. Tranquillizers of the phenothiazine type, for example, accelerated the oxidation of both substrates, whilst anti-depressant drugs (other than monoamine oxidase inhibitors) inhibited the oxidation of both substrates. 

Chlorazepate potentiates the CNS-depressant effects of phenothiazines, narcotics, barbiturates, alcohol, antihistamines, monoamine oxidase inhibitors, general anesthetics, and antidepressants. Concomitant use with cimetidine and possibly disulfiram causes diminished hepatic metabolism of chlorazepate, which increases its plasma concentration. 

General consideration oxymorphone should be started at 1/3 to 1/2 of the usual dose in patients who are concurrently receiving other CNS depressants including sedatives or hypnotics, general anesthetics, phenothiazines, tranquilizers, and alcohol, because respiratory depression, hypotension, and profound sedation or coma may result. No specific interaction between oxymorphone and monoamine oxidase inhibitors has been observed, but caution in the use of any opioid in patients taking this class of drugs is appropriate. 

Antidepressants including tricyclics, serotonin reuptake inhibitors, and monoamine oxidase inhibitors Antipsychotics drugs such as phenothiazines, haloperidol, olanzapine, or clozapine Other analgesics and anti-inflammatory agents... 

Monoamine oxidase inhibitors, phenothiazine and tricyclic antidepressants potentiate the cardiac stimulatory effects of epinephrine. AH should be stopped 1 to 2 weeks before any kind of surgery involving epinephrine. Propranolol has been reported to cause malignant hypertension and reflux bradycardia when combined with epinephrine. The possibility of this rare complication should be weighed against the necessity for using this drug in consultation with the patient s primary care physician. 

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