Promethazine Theoclate
Generic Details
Generic Name
Promethazine-Theoclate
Other Names
- Promethazine Theoclate
- Promethazine-Theophylline
Drug Class
- Antihistamine
- Antiemetic
Chemical Formula
C17H20N2S2O3
Molecular Weight
372.48 g/mol
Mechanism of Action
- Blocks histamine H1 receptors
- Antagonizes dopamine D2 receptors
Indications
- Allergic reactions
- Motion sickness
- Nausea and vomiting
Common Dosage Forms
- Tablet
- Syrup
- Injection
Typical Dosage
- 25-50 mg orally every 4-6 hours as needed
Pediatric Dosage
- Under 2 years: Not recommended
- 2-5 years: 5-15 mg orally every 4-6 hours
- 6-12 years: 10-25 mg orally every 4-6 hours
Geriatric Dosage
- Start at low end of dosing range due to increased risk of side effects
Side Effects
- Sedation
- Dizziness
- Dry mouth
- Blurred vision
- Constipation
Contraindications
- Hypersensitivity to promethazine
- Severe respiratory depression
- Coma
Pregnancy Category
- C - Risk cannot be ruled out
Lactation Safety
- Caution advised; excretion in breast milk unknown
Drug Interactions
- CNS depressants
- Anticholinergic drugs
- Monoamine oxidase inhibitors (MAOIs)
Overdose Symptoms
- Severe drowsiness
- Agitation
- Seizures
Antidote for Overdose
- None; symptomatic and supportive treatment
Storage Conditions
- Store at room temperature away from light and moisture
Pharmacokinetics
- Absorption: Well absorbed from the gastrointestinal tract
- Distribution: Widely distributed in the body, crosses the blood-brain barrier
- Metabolism: Partially hepatic via sulfoxidation and glucuronidation
- Excretion: Mainly renal as metabolites
Precautions
- Avoid use in elderly with cognitive impairment
- Use with caution in patients with asthma or respiratory conditions
Warnings
- May cause marked drowsiness; avoid driving or operating machinery
Others
- Avoid alcohol consumption while on promethazine-theoclate medication