Answer
Duphalac (lactulose) 3.335 g/5 ml oral solution has a shelf life of 2 years in HDPE containers and 3 years in other containers.
Sources for this answer
- Lactulose 3.335g/5ml oral solutionViatris (formerly Mylan or Upjohn) · emc · SmPC §6.3 Shelf life · Version 19Document updated
Sources checked