Answer
Clomethiazole’s most common side effect is nasal congestion and irritation, which may occur 15–20 minutes after ingestion and is commonest with the initial dose, decreasing in severity with subsequent doses.
Sources for this answer
- Heminevrin/Clomethiazole 192 mg CapsulesNeon Healthcare Ltd · emc · SmPC §4.8 Undesirable effects · Version 6Document updated
Sources checked