Rasalect 1 Mechanism of Action

Pharmacotherapeutic Group: Anti-Parkinson's Agent, MAO Type B. Inhibitor.
Pharmacology: Pharmacodynamics: Mechanism of Actions: Potent, irreversible and selective inhibitor of brain monoamine oxidase (MAO) type B, which plays a major role in the catabolism of dopamine. Inhibition of dopamine depletion in the striatal region of the brain reduces the symptomatic motor deficits of Parkinson's disease. There is also experimental evidence of rasagiline conferring neuroprotective effects (antioxidant, antiapop­totic), which may delay onset of symptoms and progres­sion of neuronal deterioration.
Pharmacokinetics: Duration: ~1 week (irreversible inhibition).
Absorption: Rapid.
Protein binding: 88% to 94%, primarily to albumin.
Metabolism: Hepatic N-dealkylation and/or hydroxylation via CYP1A2 to multiple inactive metabolites.
Distribution: V_dss: 87 L.
Bioavailability: ~36%.
Half-life elimination: ~3 hours (no correlation with biologic effect due to irreversible inhibition).
Time to peak, plasma: ~1 hour.
Excretion: Urine (62%, <1% of total dose as unchanged drug); feces (7%).
Toxicology: Range of Toxicity: MAO-B INIHIBITORS: Rasagiline 2 mg/day caused mild symptoms in healthy adults. Patients on chronic levodopa therapy developed hypertension and orthostatic hypotension with 10 g rasagiline.
Treatment: MAO-B INHIBITORS: Support: MANAGEMENT OF MILD TO MODERATE TOXICITY: All patients with symptoms of MAOI toxicity should be evaluated by a health care professional. Symptoms may persist for several weeks due to the irreversibility of MAO inhibition caused by these medications. Discontinuation of the offending agents and patient education involving drug interactions should be provided to all symptomatic patients.
MANAGEMENT OF SEVERE TOXICITY: Careful attention to the ABCs (airway, breathing and circulation) should guide symptomatic and supportive treatment, which is the mainstay of MAOI toxicity management.
There is no antidote for MAOI toxicity.