Monoamine Oxidase Inhibitors
- More likely to have withdrawal symptoms
- Should only be prescribed by a psychiatrist
- Patient must carry treatment card
Drugs in class
- phenelzine
- isocarboxazid
- tranylcypromine
- moclobemide - reversible inhibitor of MAOI-A, short offset, easing of
dietary restrictions
Use
- Depression which has not responded to other treatment, under close
psychiatric supervision
- Phobic anxiety
- Hysterical symptoms
- Atypical depression
Mechanism of Action
- Inhibition of A and B forms of monoamine oxidase (moclobemide only A),
leading to increased neuronal stores of NA and 5HT
Side effects
- Troublesome interactions with food and drugs
- Orthostatic hypotension, weight gain, sexual dysfunction, migraine ,
psychotic reactions, peripheral neuropathy
CNS
- Insomnia
- drowsiness
- agitation
- headache
- fatigue
- weakness
- tremor
- mania
- confusion
- convulsions
Autonomic
- blurred vision
- difficulty in micturition
- sweating
- dry mouth
- postural hypotension
- constipation
Other
- Sexual dysfunction
- weight gain
- peripheral neuropathy
- oedema
- rashes
- hepatocelullar toxicity
- leucopenia
- (Rarely) 5HT syndrome
Contraindications
- Liver Failure
- Cerebrovascular disease
- Phaeochromocytoma
- Acute confusion
- Porphyria
- Epilepsy
Interactions
- tyramine containing foods, e.g red wine, cheese
- Serious hypertensive and hyperthermic reactions
- sympathomimetic amines
- L-dopa
- Failure to metabolise drugs normally oxidised
- opiates
- cocaine
- insulin
- potentiation of oral hypoglycaemic drugs
- metabolism of carbemazepine, phenytoin may be slowed
|