Demser Side Effects

Generic name: metyrosine

Medically reviewed by Drugs.com. Last updated on Nov 25, 2023.

Note: This document contains side effect information about metyrosine. Some dosage forms listed on this page may not apply to the brand name Demser.

Applies to metyrosine: oral capsule.

Serious side effects of Demser

Along with its needed effects, metyrosine (the active ingredient contained in Demser) 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 as soon as possible if any of the following side effects occur while taking metyrosine:

More common

Diarrhea
drooling
trembling and shaking of hands and fingers
trouble in speaking

Less common

Anxiety
confusion
hallucinations (seeing, hearing, or feeling things that are not there)
mental depression

Rare

Black, tarry stools
blood in urine or stools
unusual bleeding or bruising
muscle spasms, especially of neck and back
painful urination
pinpoint red spots on skin
restlessness
shortness of breath
shuffling walk
skin rash and itching
swelling of feet or lower legs
tic-like (jerky) movements of head, face, mouth, and neck
unusual tiredness or weakness

Other side effects of Demser

Some side effects of metyrosine 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

Drowsiness

Less common

Decreased sexual ability in men
dryness of mouth
nausea, vomiting, or stomach pain
stuffy nose
swelling of breasts or unusual milk production

After you stop using this medicine, it may still produce some side effects that need attention. During this period of time, Check with your doctor immediately if you notice the following side effects:

More common

Diarrhea

Also, after you Stop taking metyrosine, you may have feelings of increased energy or you may have trouble sleeping. However, these effects should last only for two or three days.