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Imodium Multi-Symptom Relief Side Effects

Generic name: loperamide / simethicone

Medically reviewed by Last updated on Jan 4, 2024.

Note: This document contains side effect information about loperamide / simethicone. Some dosage forms listed on this page may not apply to the brand name Imodium Multi-Symptom Relief.

Applies to loperamide / simethicone: oral tablet.


  • Do not take more than the package label says or your doctor told you to take. Taking more than you were told can cause very bad heart problems, including an abnormal heartbeat. Sometimes, these heart problems can lead to death. Taking this drug with certain other drugs may also raise the chance of heart problems. Talk with your doctor.
  • Do not give to a child younger than 2 years of age.

Serious side effects

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

Other side effects

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at

For Healthcare Professionals

Applies to loperamide/simethicone: oral tablet, oral tablet chewable.


Common (1% to 10%): Constipation, flatulence, vomiting

Uncommon (0.1% to 1%): Abdominal discomfort, abdominal distention, abdominal pain, dry mouth, dyspepsia, upper abdominal pain

Rare (0.01% to 0.1%): Ileus (including paralytic ileus), megacolon (including toxic megacolon)[Ref]

Nervous system

Common (1% to 10%): Dizziness, dysgeusia, headache

Uncommon (0.1% to 1%): Somnolence

Rare (0.01% to 0.1%): Coordination abnormality, depressed level of consciousness, hypertonia, loss of consciousness, stupor

Frequency not reported: Drowsiness[Ref]


Uncommon (0.1% to 1%): Rash

Rare (0.01% to 0.1%): Bullous eruptions, erythema multiforme, pruritus, Stevens-Johnson syndrome, toxic epidermal necrolysis, urticaria[Ref]


Uncommon (0.1% to 1%): Asthenia

Rare (0.01% to 0.1%): Fatigue

Frequency not reported: Tiredness[Ref]


Rare (0.01% to 0.1%): Anaphylactic reaction, anaphylactic shock, anaphylactoid reaction, angioedema, hypersensitivity reaction[Ref]


Rare (0.01% to 0.1%): Urinary retention[Ref]


Rare (0.01% to 0.1%): Miosis[Ref]

Frequently asked questions

More about Imodium Multi-Symptom Relief (loperamide / simethicone)

Patient resources

Related treatment guides


1. Product Information. Imodium Advanced (loperamide-simethicone). Johnson and Johnson/Merck. 2006.

2. Cerner Multum, Inc. UK Summary of Product Characteristics.

3. Cerner Multum, Inc. Australian Product Information.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.