What is telmisartan?
Telmisartan (brand name Semintra®) is an angiotensin receptor blocker (ARB) used to treat high blood pressure in cats and kidney disease in cats and dogs.
Its use in cats and dogs to treat kidney disease is off label (extra label). Many drugs are commonly prescribed for off-label use in veterinary medicine. “Off label” means the drug is being used in a way that has not been reviewed or approved by the U.S. Food and Drug Administration (FDA) or Health Canada. In these instances, follow your veterinarian’s directions and cautions carefully, as they may be significantly different from those on the label.
How is telmisartan given?
- Telmisartan is given by mouth in the form of a liquid or tablet.
- It may be given with or without food but is better absorbed if given on an empty stomach. If your pet vomits or acts sick when given on an empty stomach, give future doses with food.
This medication should take effect within 1 to 2 hours; however, effects may not be noted outwardly, so laboratory tests and blood pressure measurements may be needed to evaluate this medication’s effectiveness.
What if I miss giving my pet the medication?
If you miss a dose, give it as soon as you remember, and then continue with the regular dosing schedule. However, if it is almost time for the next dose, skip the missed dose and resume the regular dosing schedule. Do not give the pet two doses at once or give extra doses.
Are there any potential side effects?
Telmisartan may cause the following side effects:
- Vomiting
- Diarrhea
- Lack of appetite
- Low blood pressure
- Decreased energy
Serious adverse reactions may occur. If any of the following signs develop, stop giving telmisartan and contact your veterinarian immediately:
- Severe tiredness
- Collapse
This short-acting medication should stop working within 24 hours, although effects can be longer in pets with liver or kidney disease.
Are there any risk factors for this medication?
DO NOT USE telmisartan in:
- Pets that are allergic to it or other similar medications
- Pets that are dehydrated
- Pets with low blood pressure
- Pets that are are pregnant
USE WITH CAUTION in:
- Pets with severe liver problems
- Pets with blood cell abnormalities
Are there any drug interactions I should be aware of?
There are several drugs that can contribute to adverse effects when given with telmisartan. Be sure to tell your veterinarian about any medications (including vitamins, supplements, or herbal therapies) that your pet is taking before starting any new treatment. If your pet inadvertently ingests any medication, let your veterinarian know immediately.
Is any monitoring needed with this medication?
- Your veterinarian will monitor your pet’s blood electrolyte levels, kidney values, and urine shortly after starting the medication and then at recommended intervals.
- Periodic monitoring of your pet’s complete blood count (CBC) and biochemistry panel (including kidney values, liver enzymes, and electrolytes) is also recommended.
- If using this medication to manage high blood pressure, your veterinarian will routinely measure your pet’s blood pressure to be sure that the medication is working.
- If using this medication to manage proteinuria, your veterinarian will routinely assess your pet’s urine protein:creatinine ratio.
- At home, monitor for any abnormal effects. If any occur, stop using the medication and contact your veterinarian.
How do I store telmisartan?
- Store telmisartan solution at room temperature, below 77°F (25°C), with the cap tightly closed.
- Tablets that are dispensed in blister packs should remain in the pack until use. Tablets that are removed from the blister pack should be used immediately.
- Consult your veterinarian on storage if your pet needs less than a full tablet per dose.
- Keep the medication out of reach of children and pets. 
What should I do in case of an emergency?
If you suspect an overdose or an adverse reaction to the medication, call your veterinary office immediately. If they are not available, follow their directions in contacting an emergency facility. Be prepared to provide information about the product and your pet's weight and symptoms.
