Can I try suppositories to relieve my baby's constipation?

1st Dietary Measures. Dr mcgraw's answer is true. But if constipated, meaning discomfort with defecation, then more dietary fiber such as prunes or vegies. Also consider if there is anything being eaten that binds the baby. For example , milk/dairy is common cause of constipation in children. Suppositoties are more a last resort in my opinion.
Yes. But likely unnecessary. Babies will often seem constipated (straining, pulling legs up) when they rally aren't. But they have irritability from having the symptom without knowing what to do about it. This is a normal baby process and will get better with age and practice of pooping. Using suppositories may work short term but create problems and dependence long term. Avoid, especially if not neede.
You may. But don't rely on them (glycerin suppositories), as the baby may ultimately require that stimulation in order to poop. Breast fed baby can go weeks without pooping, and as long as they're not uncomfortable, we don't recommend treatment. Older infants will benefit from pureed plums or plum juice, and even medications like PEG 3350 when ordered and monitored by a pediatrician.
Yes. Talk to your pediatrician first, but infant glycerin suppositories are available over the counter and can be used to soften hard stool in constipated infants.