Theophylline is a bronchodilator that is often prescribed by veterinarians to help relax the muscles in a patient’s lungs and chest so they can breathe easier. It is also commonly used to treat a wide range of pulmonary disorders, such as pulmonary edema, bronchial asthma, and chronic obstructive pulmonary disease, and in rarer cases, heart failure.


How Does Theophylline Work?

Theophylline is very effective at relaxing the muscles surrounding the airway, and clearing out the mucus that can make breathing more difficult. It helps clear out mucus build-up by increasing the movement of cilia within the airway.

Theophylline also works to strengthen the patient’s diaphragm, and this is integral in improving the patient’s ability to breathe. Theophylline not only helps the patient breathe easier, but it also helps prevent future breathing constrictions. The drug is structurally similar to caffeine, which works as a central nervous system stimulant.

Potential Side Effects of Theophylline

Theophylline is safe for use on cats and dogs when it is administered under the guidance of a veterinarian. However, the patient may still experience side effects with this drug. Most commonly, the side effects of Theophylline include central nervous system excitement, vomiting, fever, rash, and heart palpitations. In most cases, the side effects can be managed through dosage adjustments, and this will usually cause them to gradually subside over time.

However, if the patient experiences prolonged vomiting or diarrhea, or she develops hives or other signs of an allergic reaction, then she should be taken to the veterinarian as soon as possible.

Drug Interactions

Theophylline has the potential to interact with other drugs the patient may be taking. Therefore, it is important for the veterinarian to know exactly what medications the pet is currently being given.

Theophylline has known interactions with a number of different drug classes, including certain antiarrhythmics, anti-seizure drugs, certain beta-blockers, as well as cimetidine, digoxin, disulfiram, fluvoxamine, interferon, isoproterenol, and many others.

Precautions for Using Theophylline

Although Theophylline has been shown to be safe for use in veterinary medicine, the drug should be used with extreme caution in some patients. In particular, Theophylline should be used with care in patients that have been diagnosed with kidney disease, liver disease, heart disease, stomach ulcers, hyperthyroidism, or hypertension. The drug should not be prescribed to pregnant or lactating patients or horses.

Dosage and Administration of Theophylline

The dosage and administration of Theophylline varies according to the size and breed of the pet being treated, and the type and severity of their illness, but typically, the drug is taken every 6, 8, 12, or 24 hours. The drug works best when it is taken on an empty stomach and at least an hour before or two hours after eating. It can be stored at room temperature, but should be kept away from light, heat, and moisture.

Theophylline is available in a range of formulations, including tablet, capsule, and oral liquid. It is extremely important to administer the medication exactly as prescribed by the veterinarian. When administering Theophylline in tablet form, the tablet needs to be swallowed whole, not chewed.

Author: Giano Panzarella