MAOIs Cyproheptadine

Drugs that may affect venlafaxine include cimetidine, cyproheptadine, and MAOIs. Drugs that may be affected by venlafaxine include clozapine, desipramine, haloperidol, indinavir, St. John s wort, trazodone, sibutramine, sumatriptan, and warfarin. 

Serotonin syndrome SSRIs, second generation antidepressants, MAOIs, linezolid, tramadol, meperidine, fentanyl, ondansetron, sumatriptan, MDMA, LSD, St. John s wort, ginseng Hypertension, hyperreflexia, tremor, clonus, hyperthermia, hyperactive bowel sounds, diarrhea, mydriasis, agitation, coma onset within hours Sedation (benzodiazepines), paralysis, intubation and ventilation consider 5-HT2 block with cyproheptadine or chlorpromazine... 

The alleged interaction between the MAOIs and antihistamines appears to be based on a single animal study, and is probably more theoretical than real The exception seems to be cyproheptadine, which can reduce the effect of MAOIs because of its serotonin antagonist effect, see MAOIs or RIMAs + Antihistamines Cyproheptadine , below. 

Information seems to be limited to these reports but it would now be prudent to be alert for a reduction in efiicacy or an adverse response if cyproheptadine is given with any MAOI or RIMA. The manufacturer of cyproheptadine actually contraindicates concurrent used with MAOIs. However, there appears to be no reason why cyproheptadine cannot be used to treat the serotonin syndrome occurring in a patient on an MAOI. 

As with other sedative antihistamines (see MAOIs + Antihistamines , above), the UK manufacturers of cyproheptadine also say that MAOIs prolong and intensify the antimuscarinic effects of antihistamines, but fhere seems to be no clinical data to support this. 

Direct information about this interaction appears to be limited to these studies although cyproheptadine has also been found to oppose the antidepressant effects of MAOIs (see MAOIs or RIMAs + Antihistamines Cyproheptadine , p.ll31). One study suggests that not every patient is affected. If concurrent use is thou t appropriate, the outcome should be very well monitored for evidence of a reduc antidepressant response. 

---