Safety in Lactation: Skeletal muscle relaxants

This is a diverse group of drugs which may not be interchangeable for all indications. Baclofen is considered to carry the lowest risks for breastfed infants and is appropriate for use for muscle spasticity associated with multiple sclerosis or spinal cord injuries.
Cannabis extract used therapeutically contains two cannabinoids – dronabinol and cannabidol. Although the main risks to a breastfed infant exposed to cannabinoids are mainly theoretical, based on the use of marijuana, and considered to be small, they are considered to outweigh any benefits to the mother.
Where possible use short-term, intermittent dosing for diazepam to reduce infant exposure.
The clinical effectiveness of methcarbamol as a muscle relaxant is not well established.