Concerns Over Weight-Loss Medications and Neurodegenerative Diseases

Neurologists are raising alarms about the potential adverse effects of popular weight-loss medications, particularly in relation to neurodegenerative diseases like ALS.

Dr. Jinsy Andrews, a neurologist and director at NYU Langone’s ALS Center, points out that the rapid weight loss these drugs promote can clash with the biological needs of patients suffering from neuromuscular disorders.

GLP-1 agonists have proven to be effective in managing diabetes and obesity, both of which are significant health issues for many. However, Andrews highlights that the usual clinical approaches shift dramatically when it comes to treating amyotrophic lateral sclerosis (ALS).

Besides reducing some inflammation associated with obesity and diabetes, GLP-1 medications also appear to have protective effects against various health conditions, including cardiovascular disease and stroke.

But losing weight and body fat in ALS patients can actually speed up their decline. Andrews explains that for someone with ALS, weight loss can lead to a quicker progression of the condition, as the specific characteristics of the disease make calorie deficits quite harmful.

Standard guidelines for ALS treatment often recommend patients focus on maintaining or even gaining weight to preserve muscle and nerve function. “In certain situations where hypermetabolism adversely impacts the disease, losing weight can worsen symptoms,” Andrews stated.

The potential dangers were illustrated in a 2025 case report involving a 52-year-old ALS patient who was prescribed semaglutide for type 2 diabetes. Before starting the medication, her disease progressed at a known rate on the standard assessment scale. However, she lost 25 pounds in just three months and experienced a notable decline in her condition.

Once medical professionals advised her to stop taking semaglutide, her rapid descent stabilized.

Andrews emphasizes that this case, along with retrospective data from ALS patients with diabetes, highlights the need for caution when considering GLP-1 receptor agonists for treatment.

While these weight-loss medications can benefit many, experts agree it’s crucial to prioritize body weight and muscle mass for patients with neurodegenerative conditions.

“Patient safety is the highest priority for Novo Nordisk, and we take reports of adverse events seriously,” said Ambre James-Brown, head of global media at Novo Nordisk, the company responsible for drugs like Ozempic and Wegovy. “It should be noted that ALS and similar diseases aren’t listed as adverse reactions in the prescribing information for our semaglutide products.”