From the FDA Drug Label
DOSAGE AND ADMINISTRATION ... The maximum dose should not exceed 300 mg daily The maximum recommended dose of Dimenhydrinate (Dimicron) is 300 mg daily 1.
From the Research
The maximum recommended dose of dimenhydrinate for adults is 400 mg per day, typically divided into doses of 50-100 mg taken every 4-6 hours as needed. For children, dosing is weight-based and significantly lower. Adults should not exceed 400 mg in a 24-hour period as higher doses can increase the risk of side effects such as drowsiness, dry mouth, blurred vision, and in severe cases, hallucinations or cardiac issues. Dimenhydrinate works by blocking histamine H1 receptors and affecting the vestibular system, which helps control balance and reduces symptoms of motion sickness, vertigo, and nausea. The medication typically takes 20-30 minutes to start working and its effects last about 4-6 hours. If you're taking other medications, especially other antihistamines, sedatives, or alcohol, be cautious as these can compound the sedative effects of dimenhydrinate. Always consult with a healthcare provider before taking maximum doses, especially if you have underlying health conditions.
Some key points to consider when taking dimenhydrinate include:
- The risk of side effects increases with higher doses, so it's essential to follow the recommended dosage guidelines 2.
- Dimenhydrinate can interact with other medications, such as sedatives and antihistamines, which can increase the risk of adverse effects 3.
- The medication's efficacy in reducing motion sickness symptoms has been demonstrated in various studies, including a randomized, placebo-controlled study comparing two formulations of dimenhydrinate 4.
- Dimenhydrinate's effects on the vestibular system and its potential to alleviate vertigo and nausea have been explored in studies, including one that evaluated the effects of TTS-scopolamine, dimenhydrinate, lidocaine, and tocainide on motion sickness, vertigo, and nystagmus 5.
It's crucial to prioritize caution when taking dimenhydrinate, especially if you have underlying health conditions or are taking other medications. Always consult with a healthcare provider before taking maximum doses or if you have any concerns about the medication's effects.