All medications (human and veterinary) have the potential to cause side effects. Your veterinarian always considers these potential side effects when prescribing a medication, with the goal of maximizing the positive effects of the drug and minimizing the unwanted side effects. However, certain pets may be more sensitive to the side effects of one or another individual medication. Often, a dose reduction is sufficient to eliminate side effects, although in some cases the lower dose may be less effective. In other cases, a medication with a similar mode of action can be substituted for the problematic drug. If you are concerned that a medication you are giving be creating a side effect then you should call your veterinarian who can help determine the best course of action.
Difficulty getting medications into some dogs, and especially in cats, can become a major problem. Inability to administer medications can complicate successful treatment of heart disease. Cats who dislike medication administration can change the way they interact with family members, running away at pill time and becoming less interactive with the family. Methods to administer pills can include hiding them in food or treats (see the Diet section), direct administration of the pill into the back of the throat, or changing the formulation of the medication. Liquid formulation can be made for oral administration of many cardiac medications, although some medications (for example, pimobendan) are reportedly unstable when compounded into a liquid formulation by compounding pharmacies. Application of special formulations of some medication to the skin has been studied in cats (transdermal medication), however most studies indicate that the absorption of most of the cardiac drugs is unpredictable and transdermal cardiac medications are generally not recommend in our practice.