Drug | Dose as-needed |
Orally administered agents: | |
Antihistamines, first-generation | |
Dimenhydrinate | 50 mg every 4 to 6 hours |
Diphenhydramine | 25 to 50 mg every 4 to 6 hours (maximum daily dose 200 to 300 mg) |
Meclizine | 12.5 to 50 mg every 6 to 12 hours (maximum daily dose 100 mg) |
Benzodiazepines | |
Alprazolam | 0.5 mg immediate release every 8 hours |
Clonazepam | 0.25 to 0.5 mg every 8 to 12 hours |
Diazepam | 1 to 5 mg every 12 hours |
Lorazepam | 1 to 2 mg every 8 hours |
Benzodiazepines should not be used for more than 2 to 3 days for acute vertigo treatment | |
Antiemetics* | |
Metoclopramide | 5 to 10 mg every 6 hours |
Ondansetron¶ | 4 mg every 8 to 12 hours |
Prochlorperazine | 5 to 10 mg every 6 hours |
Promethazine | 12.5 to 25 mg every 4 to 6 hours |
Parenterally administered agents for acute emergency ward use:Δ | |
Antihistamines, first-generation | |
Diphenhydramine | 10 to 50 mg IV |
Dimenhydrinate | 50 mg IV |
Antiemetics* | |
Metoclopramide | 10 mg IV |
Ondansetron¶ | 4 to 8 mg IV |
Prochlorperazine | 2.5 to 10 mg IV |
Promethazine | 12.5 to 25 mg IM or IV (vesicant, use caution with IV administration; refer to drug monograph included within UpToDate) |
IM: intramuscular; IV: intravenous.
* Rare adverse cardiac reactions have been described with most antiemetics, particularly following parenteral use. These agents should be avoided in patients with known QT interval prolongation or other risk factors for torsades de pointes (TdP; eg, hypomagnesemia, hypokalemia). Refer to topic review of acquired long QT syndrome, section on drug-induced TdP within UpToDate. Phenothiazines and metoclopramide can cause extrapyramidal side effects (eg, akathisia, dystonia), particularly with parenteral use. Refer to accompanying text.
¶ Other serotonin 5HT3 antagonist antiemetics (eg, dolasetron, granisetron) may be used if ondansetron is not available.
Δ If IV access is unavailable, these agents may be administered IM. However, with the exception of promethazine, IM use is not preferred due to injection site pain.Do you want to add Medilib to your home screen?