Answer
Some preparations contain sucrose. Sugar-free products instead contain maltitol and sorbitol, which are unsuitable in hereditary fructose intolerance.
Sources for this answer
- Simple Linctus Sugar Free — Current selected SmPCemc · Summary of Product Characteristics
- Simple Linctus Paediatric Sugar Free — Current selected SmPCemc · Summary of Product Characteristics
- Simple Linctus Paediatric BP — Current selected SmPC