What is Promethazine?
Promethazine is an oral tablet that helps treat nausea, vomiting, and dizziness. This is useful to treat:
- BPPV
- Meniere’s disease
- symptoms caused by vestibular neuritis (also called labyrinthitis), which is a type of inner ear infection.
There’s no cure for BPPV or Meniere’s; the treatments only help resolve the symptoms.
How does Promethazine work?
Promethazine belongs to the drug class phenothiazines. It works by blocking dopamine, histamine, and acetylcholine signals in the brain. These actions help reduce dizziness, nausea, and vomiting, which makes it useful in conditions like BPPV and Meniere’s.[1]
Will I get side effects using Promethazine?
Yes, you might get side effects while taking Promethazine, although not everyone will get them, such as:
- Dry mouth
- Blurred vision
- Drowsiness
- Headaches
- Stomach problems
- Dizziness
- Confusion
- Sensitivity to the sun
These side effects should not last more than a few days; if they do, contact your doctor immediately.
Does Promethazine make you sleepy?
Yes, you might feel sleepy or drowsy while taking Promethazine.
Promethazine is a first-generation antihistamine; these medicines are known to cause drowsiness as they enter the brain, causing sedation. If you feel sleepy or drowsy, don’t drive or operate heavy machinery.[2]
What doses of Promethazine are there?
Promethazine is available in three doses: 12.5 mg, 25 mg, and 50 mg. The typical dose is one 25 mg tablet at night, followed by one tablet every six to eight hours as needed. Your doctor can increase your dose if your symptoms are severe.
Your doctor will provide you with more information on the specific dosage you need, based on your medical history and symptoms.
Treated trusted source:
- Southard BT, Al Khalili Y. Promethazine. [Updated 2024 Jan 1]. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2025 Jan-.
- Farzam K, Sabir S, O’Rourke MC. Antihistamines. [Updated 2023 Jul 10]. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2025 Jan-.
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