If you are having any type of surgery, be sure the surgeon knows ahead of time that you are using this medicine. Atenolol can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert. Animals. Medical records from the University of Missouri Veterinary Medical Teaching Hospital and the University of Minnesota Veterinary Medical Center were reviewed to identify dogs that were diagnosed with severe SAS between September 1999 and January 2011. Atenolol is a β 1-selective blocking agent and is the most commonly used β-blocker in veterinary medicine. Because it is β 1 -selective, it has less potential to cause or contribute to bronchospasm in predisposed dogs and cats, although the β 1 -selectivity is likely limited or absent at high doses. Author information: (1)Department of Veterinary Clinical Sciences, College of Veterinary Medicine, The Ohio State University, 601 Vernon L Tharp Street, Columbus, OH 43210, USA. schober.4@osu.edu OBJECTIVES: To investigate the effect of treatment with atenolol on 5-year survival in cats with preclinical hypertrophic cardiomyopathy (HCM). Dr. Barbara Forney is a veterinary practitioner in Chester County, Pennsylvania. She has a master's degree in animal science from the University of Delaware and graduated from the University of Pennsylvania School of Veterinary Medicine in 1982. In veterinary medicine, the most common potential side effects of atenolol are decreased heart rate, general weakness, loss of appetite, and low blood pressure. In some cases, the patient may faint, but such instances are rare. If your pet faints after taking atenolol, contact your veterinarian immediately. Mark G. Papich DVM, MS, DACVCP, in Saunders Handbook of Veterinary Drugs (Fourth Edition), 2016. Indications and clinical uses. Atenolol is one of the most commonly administered beta blockers for dogs and cats. Atenolol is a beta blocker that is used to control the heart rate of cats and dogs with irregular heart rhythms. Come to petMD for a complete list of pet medications and prescriptions. Human Resources for the University of Oklahoma. Serving Faculty and Staff in Norman, Oklahoma City, and Tulsa campuses. Atenolol is not FDA approved for use in veterinary medicine; however, it is a commonly accepted practice for veterinarians to prescribe this medication for dogs and cats. Atenolol is also used to lower blood pressure and to treat enlarged hearts in cats.