Answer
Very rare gastrointestinal adverse effects reported with Benylin Herbal Cough & Cold Sugar Free Syrup include diarrhoea, epigastric discomfort, nausea or vomiting, and dysphagia (difficulty swallowing).
Sources for this answer
- Benylin Herbal Cough & Cold Sugar Free SyrupMcNeil Products Ltd · emc · SmPC §4.8 Undesirable effects · Version 1Document updated
Sources checked