The winter solstice on June 21 is named ALS/MND Global Awareness Day for its symbolic potential as a turning point in managing this debilitating and incurable disease that claims around 550 Australians annually.
Riluzole is the only medicine yet approved to treat amyotrophic lateral sclerosis (ALS), also known as Motor Neurone Disease (MND). It is thought that riluzole blocks neurotransmission of glutamate to prevent injury of vulnerable motor neurons. It preserves quality of life by slowing disease progression, and modestly extending survival.
The 50mg tablets are taken twice daily regardless of the wide variability in clearance (particularly noted in smokers, Japanese, and patients with hepatic impairment). It should not be taken with meals high in fat; or used by patients with hepatic impairment, or who are pregnant or lactating.
As excretion is mostly via cytochrome P450 dependent metabolism, potential inhibitors of CYP 1A2 could decrease, while inducers could increase, the rate of riluzole elimination. It isn’t known if riluzole in turn affects the metabolism of these drugs.
Weakness, nausea, and elevations in liver function tests are the most commonly reported adverse reactions, and patients should be warned of the risk of dizziness, vertigo or somnolence.
Patients should be monitored for hepatic toxicity, neutropenia, and interstitial lung disease.
A neurologist may initiate PBS Authority Prescriptions for newer patients who are yet to be severely affected.