Symptoms of postpartum depression are similar to what happens normally following childbirth. They include difficulty sleeping, appetite changes, excessive fatigue, decreased libido, and frequent mood changes.
If your horse needs a topical medication along with a pain reliever, your veterinarian may have you apply a dimethyl sulfoxide, or DMSO, solution. DMSO is quickly absorbed through the skin and is especially good at relieving swelling, as it pulls moisture from tissues.
Generally speaking, the strongest pain medication available is fentanyl. It is a synthetic version of opiate and is only administered by injection. It is usually found only in hospitals where it helps induce sleep in patients suffering from extreme levels of pain.