Miglustat Side Effects

Medically reviewed by Drugs.com. Last updated on Mar 13, 2025.

Applies to miglustat: oral capsule.

Serious side effects of miglustat

Along with its needed effects, miglustat may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur while taking miglustat:

More common side effects

• black, tarry stools
• bleeding gums
• blood in the urine or stools
• burning, crawling, itching, numbness, prickling, "pins and needles", or tingling feelings
• diarrhea
• pinpoint red spots on the skin
• trembling or shaking in the hands
• unsteadiness or awkwardness
• unusual bleeding or bruising
• weakness in the arms, hands, legs, or feet
• weight loss

Less common side effects

• chest tightness
• fast, pounding, or irregular heartbeat or pulse
• increase blood pressure
• lower back or side pain

Other side effects of miglustat

Some side effects of miglustat may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects.

Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

More common side effects

• back pain
• bloated or full feeling
• blurred or loss of vision
• difficulty having a bowel movement (stool)
• disturbed color perception
• dizziness
• double vision
• dry mouth
• excess air or gas in the stomach or intestines
• halos around lights
• headache
• heartburn
• heaviness in the limbs
• indigestion
• leg cramps
• loss of appetite
• memory loss
• menstrual changes
• nausea
• pain or discomfort in the chest, upper stomach, or throat
• passing gas
• stomach discomfort, upset or pain
• swelling of the abdominal or stomach area
• tunnel vision
• unsteady walk
• vomiting

Less common side effects

• change in taste
• constipation
• joint or muscle pain
• lack or loss of strength
• loss of taste
• pressure in the stomach
• stomach discomfort, upset, or pain
• swelling of the stomach area

For healthcare professionals

Applies to miglustat: oral capsule.

General adverse events

The most commonly reported adverse reactions included diarrhea, flatulence, abdominal pain, weight loss, and tremor; the most common serious adverse reaction was peripheral neuropathy; diarrhea and tremor were the side effects that most commonly required intervention.^[Ref]

Gastrointestinal

• Very common (10% or more): Diarrhea (including osmotic diarrhea; up to 100%), abdominal pain (up to 67%), flatulence (up to 50%), nausea (up to 22%), vomiting (up to 11%)
• Common (1% to 10%): Constipation, dry mouth, dyspepsia, epigastric pain not food-related, bloating, stomach pain, gas, abdominal distension/discomfort
• Frequency not reported: Dysphagia, indigestion, dry mouth^[Ref]

Osmotic diarrhea appears to be due to inhibitory activity of miglustat on intestinal disaccharidases leading to reduced absorption of dietary disaccharides in the small intestine. Diarrhea decreased over time with continued therapy.^[Ref]

Metabolic

• Very common (10% or more): Weight decrease (up to 67%)
• Common (1% to 10%): Anorexia^[Ref]

Weight loss has been observed in approximately 55% to 65% of patients. Peak weight loss occurs between 6 and 12 months, with a mean weight loss of 6% to 7% of body weight. It is unclear if weight loss results from the diarrhea and associated gastrointestinal complaints, a decrease in food intake, or a combination of these or other factors. There is a trend to return to baseline weight after the first year.^[Ref]

Nervous system

• Very common (10% or more): Tremor/exacerbation of existing tremor (about 30%), headache (up to 22%), tremor (up to 17%), dizziness (up to 11%)
• Common (1% to 10%): Unsteady gait, paresthesia, migraine, peripheral neuropathy, ataxia, hypoesthesia
• Frequency not reported: Gait abnormal, gait spastic, hyperreflexia^[Ref]

The most common serious adverse reaction in clinical trials was peripheral neuropathy. Tremor, and worsening tremor were very commonly reported. Compared to the general population, patients with type 1 Gaucher disease are more likely to have peripheral neuropathy. A patient should be evaluated for tremor and neuropathy prior to starting therapy.^[Ref]

Other

• Very common (10% or more): Generalized weakness (up to 17%)
• Common (1% to 10%):Fatigue, asthenia, chills, malaise, pain
• Frequency not reported: Fatigue, lacerations^[Ref]

Ocular

• Very common (10% or more): Visual disturbances (up to 17%)^[Ref]

Musculoskeletal

• Very common (10% or more): Cramps (up to 11%)
• Common (1% to 10%): Muscle spasms
• Frequency not reported: Leg cramps, muscle cramps, back pain, heaviness in arms and legs^[Ref]

Psychiatric

• Common (1% to 10%): Memory loss
• Frequency not reported: Insomnia, decreased appetite, depression, decreased libido^[Ref]

Hematologic

• Common (1% to 10%): Thrombocytopenia
• Frequency not reported: Mild reduction in platelet count^[Ref]

Genitourinary

• Common (1% to 10%): Menstrual disorder^[Ref]

Respiratory

• Frequency not reported: Nasopharyngitis, cough, sinusitis^[Ref]

Further information

Miglustat side effects can vary depending on the individual. Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Note: Medication side effects may be underreported. If you are experiencing side effects that are not listed, submit a report to the FDA by following this guide.

Medical Disclaimer