US Pharm. 2022;47(1):15-16.
Known as Lou Gehrig’s Disease
Amyotrophic lateral sclerosis (ALS) is a rare and fatal neurologic disease. In the United States, approximately 5,000 people will be newly diagnosed with ALS every year. Half of all patients diagnosed with ALS will die within 2 to 5 years of onset. However, some people survive more than 10 years after diagnosis. In ALS, the brain loses connections to and the ability to control the muscles of the body. ALS can result from the presence of specific genetic risk factors. For 10% of these individuals, the disease is also found in another family member. There is no known family history for the other 90% of people with ALS.
Motor Neurons Break Down, Die
Motor neurons run from the brain to the muscles through the spinal cord. They are responsible for all voluntary body movements and muscle control. In ALS, these motor neurons break down until they die. When the neurons die, they can no longer carry signals from the brain to the muscles and back. ALS is also known as Lou Gehrig’s disease, after a well-known baseball player who died in 1941 from the condition.
Difficulty Speaking, Moving, Eating, and Breathing
Loss of muscle control can make it difficult for people with ALS to speak, move, eat, or even breathe. Onset typically occurs in middle age between the ages of 40 and 65 years. It has a slightly higher rate in men than in women. Symptoms of ALS develop gradually and are marked by muscle weakness and muscle wasting. The symptoms of early ALS are different from person to person depending on the neurons affected and which part of the body the neurons control. For instance, degeneration of the motor neurons in the arm and hand can make it challenging to write or lift a cup of coffee. In comparison, degeneration of the neurons controlling the vocal cords may make speaking difficult.
ALS is progressive, affecting more neurons over time, leading to increasingly diverse and severe symptoms and ultimately death. The disease progression can also be different from one person to the next. All people with ALS will have muscle weakness and, eventually, paralysis. The neurons associated with the senses of smell, taste, touch, sight, and hearing are not affected. Those with advanced stages of ALS will ultimately require ventilator support to breathe, and respiratory failure is the most common cause of death.
Treatment Available, but Not Curative
There are currently three drugs approved by the FDA for the treatment of ALS: Rilutek (riluzole, available in tablets, oral suspension, and oral film formulations), Radicava (edavarone), and Nuedexta (dextromethorphan HBr and quinidine sulfate).
Riluzole works by interfering with the activity of glutamate, one of the chemical messengers that transmit signals between nerve cells. In ALS, there is an elevated level of glutamate, which is toxic to nerve cells. Riluzole is not a curative treatment for ALS. Still, it has been shown to prolong survival and slow the progression of the disease. The most common side effects are dizziness, gastrointestinal symptoms, and liver-function changes.
Edavarone is a medication that can reduce the effects of oxidative stress resulting from motor-neuron breakdown. It can also slow the rate of decline in ALS patients. Edavarone is administered by infusion into a vein, typically for 10 to 14 days in a row, once a month. Side effects may include walking problems, bruising, headaches, and allergic reactions.
Lastly, Nuedexta, a combination of dextromethorphan and quinidine (DMQ), is unique because it specifically treats pseudobulbar affect (PBA), which is a condition in people with ALS causing sudden and unpredictable episodes of crying or laughing. DMQ is thought to work in the brain region responsible for the function of the bulbar muscles (the muscles responsible for speech and swallowing) and helps reduce PBA episodes.
If you have questions about medications used to treat ALS, including dosing and side effects, ask your local pharmacist or other healthcare practitioner.
The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.
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