Dimenhydrinate Side Effects

Medically reviewed by Drugs.com. Last updated on Jun 10, 2025.

Applies to dimenhydrinate: oral solution, oral tablets, parenteral injection.

Side effects include:

Drowsiness, headache, blurred vision, tinnitus, dryness of the mouth and respiratory passages, incoordination, palpitation, dizziness, hypotension.

Paradoxical CNS stimulation in pediatric patients and occasionally in adults.

With IM injection: Pain at the injection site.

Because dimenhydrinate contains diphenhydramine, the possibility of other diphenhydramine-related adverse effects should also be considered.

For healthcare professionals

Applies to dimenhydrinate: compounding powder, injectable solution, oral liquid, oral tablet, oral tablet chewable.

General adverse events

The most frequently reported adverse reaction is drowsiness.^[Ref]

Cardiovascular

• Frequency not reported: Tachycardia^[Ref]

Dermatologic

• Frequency not reported: Skin rash^[Ref]

Gastrointestinal

• Frequency not reported: Dry mouth, epigastric distress, nausea^[Ref]

Genitourinary

• Frequency not reported: Difficult or painful urination^[Ref]

Metabolic

• Frequency not reported: Anorexia^[Ref]

Nervous system

• Frequency not reported: Drowsiness, dizziness, headache, excitation^[Ref]

Ocular

• Frequency not reported: Blurred vision^[Ref]

Other

• Frequency not reported: Lassitude^[Ref]

Psychiatric

• Frequency not reported: Nervousness, restlessness, insomnia^[Ref]

Respiratory

• Frequency not reported: Dry nose, dry throat, thickening of bronchial secretions^[Ref]

See also:

Further information

Dimenhydrinate 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