From the FDA Drug Label
2.1 Recommended Dosage The recommended dosage is 25 mg to 100 mg daily administered orally, in divided doses, depending upon clinical response. The recommended dose of meclizine for treating dizziness, specifically vertigo associated with diseases affecting the vestibular system, is 25 mg to 100 mg daily administered orally, in divided doses, depending upon clinical response 1.
- The dose may be adjusted based on the patient's clinical response.
- Meclizine should be taken as directed by a healthcare professional.
From the Research
The recommended dose of meclizine for treating dizziness is typically 25 to 50 mg taken by mouth up to three times daily as needed. This dosage is supported by the most recent and highest quality study, which found that single-dose antihistamines, such as meclizine, provide greater vertigo relief at 2 hours than single-dose benzodiazepines 2.
Key Points to Consider
- Meclizine works by blocking histamine H1 receptors in the brain, which helps reduce the sensitivity of the vestibular system and suppresses signals to the vomiting center.
- The antihistamine has a relatively long half-life of about 6 hours, allowing for less frequent dosing compared to some other anti-vertigo medications.
- Common side effects may include drowsiness, dry mouth, and blurred vision, so patients should avoid driving or operating machinery until they know how the medication affects them.
- Elderly patients may need to start with a lower dose (12.5 mg) due to increased sensitivity to side effects.
- Meclizine should be used with caution in patients with glaucoma, prostatic hypertrophy, or urinary retention due to its anticholinergic properties.
Evidence-Based Recommendation
The study published in JAMA Neurology in 2022 2 provides the most recent and highest quality evidence for the use of meclizine in treating dizziness. This systematic review and meta-analysis found that single-dose antihistamines result in significantly more improvement on 100-point VAS scores compared with benzodiazepines. However, the evidence did not support an association of benzodiazepine use with improvement in any outcomes for acute vertigo.
Important Considerations
- Other studies, such as the one published in The Journal of Emergency Medicine in 2017 3, found that meclizine and diazepam are equally effective in the treatment of vertigo.
- However, the 2022 study 2 provides the most recent and comprehensive evidence for the use of meclizine in treating dizziness.
- Patients should be advised to take the medication as needed and to follow the recommended dosage to minimize side effects.