Here's a great article about NSAIDS and what to ask your vet before your pup starts taking them, as well as what side effects to watch out for:

Key Things to Ask Before Giving Your Dog NSAIDs

Before using any drug on your dog (including NSAIDs), make sure you understand:

• What the drug is being used for.
• The dose rate for your dog – how much to give and how often.
• How to give the drug – for example, with or without food.
• How long to keep treating your dog – determine if the drug is for short term treatment or if it can be safely be used for the long term.
• How often your dog needs to be checked by your vet.
• Whether there are any interactions between the drug and your dog’s other treatments.
• What the side effects might be from taking the drugs.
• You can obtain all this information from your vet, who is the only one who can prescribe these drugs for your dog.

Potential Side Effects – What to Look Out For
While NSAIDs are helpful drugs that will ease your dog’s suffering, they can also cause several unpleasant side effects if you are not careful. A major side effect of NSAIDs is irritation to the upper gastrointestinal tract leading to ulceration and bleeding. Signs of this are:

• Lack of appetite.
• Depression and lethargy.
• Vomiting, especially if the vomit looks like coffee grounds. Coffee ground vomit is produced when there is blood that has been digested by stomach acid.
• Black sticky feces – again the result of blood in the stomach being digested as it moves down the gastrointestinal tract.

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