The two categories to treat inflammation and other conditions are steroids and NSAIDS (non-steroidal anti-inflammatory drugs). Because there are many side effects with the use of steroids, I felt it would be interesting to review them here. This isn't to scare anyone away from steroids, as they are an essential drug and used to effectively treat many conditions.
Many things produce inflammation, such as bacteria, viruses, fungi, trauma, allergies, and neoplasias (tumor growth or growth of new tissue). Trauma itself can be defined as occurring outside the body (what we tend to think of) or inside the body, such as an allergy or reaction to a chemical.
One of the defenses our body mounts in response to inflammation is the release of hydrocortisone from the adrenal cortex, with the help of the hypothalmus and the pituitary gland. The adrenal cortex produces and releases 2 key hormones: mineralcorticoids and glucocorticoids. Ah, now these words sound familiar I bet! Steroid therapy replicates these naturally occurring hormones, while I bet some people weren't sure that they are already naturally produced in the body, and the drug therapy mimics their effects.
Without going into too many boring, technical details, understand that these naturally occurring hormones do many things when everything is working as it should. From metabolizing food into energy and/or suppressing the body's way it produces pain and inflammation.
Steroids can be used for patients with arthritic conditions; a steroid can be injected directly into the site of pathology, avoiding many negative side effects. The main disadvantage is a condition called "crystalline arthropathy", where the steroid suspension can settle out in the joint, but that effect is treatable.
There are many side effects of steroidal therapy. A large concern stems from the fact that we are administering drugs to the dog which the body should be naturally producing. This can inspire the body to stop producing those chemicals itself. This is why steroid treatment must be weaned down, and can never be stopped suddenly. By slowly removing your pet from the drug, it allows the body time to "kick back in" and produce appropriate levels itself. By avoiding this key aspect of steroidal use, we can create diseases in our pets such as Addison's Disease (hypoadrenalcorticism) or Cushing's Disease (hyperadrenalcorticism).
Other side effects can include immunosupression, so if your animal is healing from some other injury, while on steroids that process will be slowed down. A suppressed immune system also means they have a diminished natural ability to fight things off in general. They may have an increased appetite in addition to muscle wasting. GI irritation and ulcers are a potential problem, but they are a potential side effect of pretty much all drug use. You may see some hair loss due to the break down of proteins in the hair follicle.
If your vet prescribes a steroid for the treatment of your dog's condition, review all the potential side effects in detail with them. Always follow the treatment regimen closely, and never abruptly stop giving your dogs steroids unless advised by your vet.