Rasagiline is a new medication which is used to treat Parkinson's disease either as monotherapy (by itself) or in addition to levodopa therapy. Rasagiline was developed in Israel by Teva Pharmaceuticals. How does rasagiline work?
In Parkinson's disease there is a loss of cells producing dopamine in certain areas in the brain. Rasagiline (Azilect) promotes increased and sustained levels of dopamine in these areas. Rasagiline does this by selectively inhibiting an enzyme called monoamine oxidase-B. This enzyme breaks down dopamine in the central nervous system. Inhibition of monamine oxidase-B reverses the depletion of dopamine, which is responsible for symptoms of Parkinson's disease such as tremor, slowness of movement and rigidity.
The main advantage of rasagiline over medications with similar mechanisms of action such as selegiline is that rasagiline breaks down and is eliminated in the body without producing any undesirable metabolites.
Several studies have shown that rasagiline (Azilect) holds much promise for Parkinson's patients. The LARGO trial showed that patients treated with rasagiline experienced an average reduction in "off" time of 1.2 hours daily when compared to placebo. They also showed significant improvement in the major symptoms of Parkinson's disease.
The PRESTO study showed that patients treated with rasagiline (Azilect) experienced an average reduction in "off" time of 1.85 hours daily, a significant reduction compared to placebo. Rasagiline significantly improved the Parkinson's symptoms when compared to the placebo group. Click here for more information about the PRESTO study.
What is the usual dosage of rasagiline?
Rasagiline (Azilect) is available as a 1mg tablet. The usual dosage is 1mg per day, taken with or without food. There is no need to adjust the dosage for elderly patients. Any patients with liver function impairment should not take rasagiline. There does not need to be an adjustment of dosage for patients with kidney function impairment.
Does rasagiline interact with any other medications?
Patients taking MAO (monoamine oxidase) inhibitors or pethidine should not take rasagiline (Azilect). There should be a minimum of 14 days from the stoppage of rasagiline and the beginning of treatment with MAO inhibitors or pethidine.
Rasagiline should not be administered at the same time as fluoxetine or fluvoxamine. Use of rasagiline with any other antidepressants should be approached with caution. Dextromethorphan or decongestants such as pseudoephedrine should also be avoided.
Because of the manner rasagiline is removed from the body, there may also be interactions with medications such as ciprofloxacin, theophylline, entacapone, and other medications. Before starting rasagiline, patients should inform their prescriber of all medications that they take.
Does Rasagiline have any side effects?
Rasagiline (Azilect) is generally well tolerated. However, all medications can potentially have side effects. Some side effects that appeared in clinical trials with rasagiline include: headache, flu-like symptoms, malaise, neck pain, stomach irritation, depression, conjunctivitis, postural hypotension, constipation, vomiting, weight loss, joint pain, abdominal pain, and dyskinesia. This is not a complete list, but a list of some of the more common side effects reported.
What about rasagiline in pregnancy?
There are no documented studies regarding the use of rasagiline in pregnancy or in breast-feeding mothers.