Meclizine Dosage for Vertigo
The recommended dosage of meclizine for treating vertigo is 25 mg to 100 mg daily, administered orally in divided doses, depending upon clinical response. 1
Dosing Guidelines
- Standard dosing: 25-100 mg daily in divided doses
- Common starting dose: 25 mg orally
- Frequency: Can be taken once daily or divided into multiple doses
- Duration: Should be limited to short-term use (<1 week) to avoid interference with vestibular compensation 2
Administration Considerations
- Meclizine tablets must be swallowed whole 1
- Onset of action is typically about 1 hour after oral administration 3
- A suspension formulation may provide more rapid onset of action compared to tablets 3
- Effects may last 8-24 hours, depending on the individual
Efficacy and Comparisons
- Meclizine (25 mg) and diazepam (5 mg) have been shown to be equally effective in treating acute peripheral vertigo in emergency department settings 4
- In clinical trials, meclizine 25 mg twice daily for 5 days has demonstrated efficacy for vertigo of different origins 5
Important Precautions
- Drowsiness warning: Patients should be cautioned against driving or operating dangerous machinery while taking meclizine 1
- Alcohol interaction: Patients should avoid alcoholic beverages while taking meclizine due to potential increased CNS depression 1
- Use with caution in patients with:
- Asthma
- Glaucoma
- Enlargement of the prostate gland
- Due to potential anticholinergic effects 1
Common Side Effects
- Drowsiness (most common)
- Dry mouth
- Headache
- Fatigue
- Vomiting
- Blurred vision (rare) 1
Drug Interactions
- Increased CNS depression when administered with other CNS depressants, including alcohol 1
- Potential interactions with CYP2D6 inhibitors, as meclizine is metabolized by this enzyme 1
- CYP2D6 genetic polymorphism may contribute to large interindividual variability in response 3
Special Populations
- Pregnancy: Limited data available; use only if benefits outweigh potential risks 1
- Elderly patients: May be at higher risk of falls and may require dose adjustment 2
Remember that vestibular suppressants like meclizine should be limited to short-term use (less than one week) to prevent interference with natural vestibular compensation mechanisms, as recommended by the American Academy of Otolaryngology-Head and Neck Surgery 2.