From the FDA Drug Label
6 ADVERSE REACTIONS The following adverse reactions associated with the use of meclizine hydrochloride were identified in clinical studies or postmarketing reports. Because some of these reactions were reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure. Anaphylactic reaction, drowsiness, dry mouth, headache, fatigue, and vomiting. On rare occasions blurred vision has been reported.
The FDA drug label does not answer the question.
From the Research
Meclizine overdose requires immediate medical attention, and treatment should involve supportive care in a hospital setting, possibly including activated charcoal to reduce absorption if the overdose was recent, as supported by the most recent and highest quality study on the use of activated charcoal in poisoning 1. If you suspect someone has overdosed on meclizine, call poison control (1-800-222-1222) or emergency services (911) immediately. Symptoms of overdose may include extreme drowsiness, confusion, hallucinations, dilated pupils, dry mouth, flushing, fever, rapid heartbeat, difficulty urinating, seizures, and in severe cases, coma.
Key Considerations
- The severity of meclizine overdose depends on the amount ingested, time since ingestion, and individual factors like age and health status.
- Meclizine is an antihistamine commonly used for motion sickness and vertigo, and overdose occurs when someone takes significantly more than the recommended dose (typically 25-50mg per day for adults).
- There is no specific antidote for meclizine overdose, and treatment is focused on supportive care and management of symptoms.
- Prevention of accidental overdose is crucial, and all medications, including over-the-counter drugs like meclizine, should be kept out of reach of children and in their original containers.
Treatment Approach
- Activated charcoal may be administered to reduce absorption if the overdose was recent, as suggested by the systematic review on the use of activated charcoal in poisoning 1.
- IV fluids, cardiac monitoring, and management of specific symptoms may also be part of the treatment approach.
- The use of flumazenil, a benzodiazepine antagonist, is not recommended for meclizine overdose, as it is not a benzodiazepine, and its use is not supported by the available evidence 2, 3.
Important Reminders
- Meclizine overdose can have serious consequences, and prompt medical attention is essential to prevent long-term harm or death.
- Regular use of meclizine or other medications should be carefully monitored, and patients should be aware of the risks of overdose and dependence, as highlighted in the study on benzodiazepines 4.