Interactions at receptor sites

1. MAOIs-sympathomimetic agents

- MAO acts to break down catecholamines (norepinephrine) since enzyme is
dysfunctional, concentration of its within adrenergic neurons increase and
these drug may intervene to break down.

2. MAOIs-tricyclic antidepressants

- Atropine-like reaction, tremors, convulsions, hyperthermia and vascular
collapse resulted the combination use of MAOI with tricyclic antidepressants.

3. MAOIs-SSRI

- Combined both agent lead to death report said. SSRI (citalopram, escitalopram,
fluoxetine, fluvoxamine, paroxetine, sertaline) with MAOI is contraindicated.
Fluoxetine has a long life concentration in the blood when used for the first
line may take 5 weeks to yield for excretion before administrating MAOI.

4. Guanethidine-tricyclic antidepressants

- Guanethidine site action is adrenergic neuron and may uptake norepinephrine
as well as indirectly acting to ephedrine and amphetamine.
- It plays anti hypertensive action. Even showed that antipsychotic agent may
inhibit guanethidine (chlorpromazine) and haloperidol then other agents like
tricyclic antidepressants reduce the antihypertensive effects of guanethid