Atenolol is a beta blocker commonly used by veterinarians to treat specific heart rhythm problems, hypertension, or hypertrophic cardiomyopathy in cats. This class of drugs works to block the beta specific receptors which in turn can reduce symptoms such as artificially increased blood sugar, a too-fast heart rate, and increased blood pressure – similar to the effects of an ‘adrenalin rush’. Atenolol usually works to reduce cardiac output, lower high blood pressure, and slow the heart rate. Because of this, it can be beneficial for pets with conditions like hypertrophic cardiomyopathy, and even provide cardioprotection in heart diseases like dilated cardiomyopathy.
Interesting Summary Points:
- Using beta blockers in cats with HCM did not influence symptoms
- Using beta blockers in cats with HCM did not extend or shorten life
- Beta blockers did reduce blood pressure and reduce heart rate which are desirable in HCM cases
- Beta blockers are well tolerated by cats and their dosing is pretty consistent and well worked out.
- Metoprolol is, at this writing, discontinued.
It is important to note that this prescription medication can only be obtained from a veterinarian or by prescription, and may cause pets to become weak due to its effects on heart rate and low blood pressure. Therefore, Atenolol may need to be used with caution in animals with heart failure, and caution should be taken when mixing it with other medications like furosemide, insulin, and calcium channel blockers drugs (diltiazem, verapamil, amlodipine). If a pet collapses while receiving Atenolol, it should be immediately reported to a veterinarian.
Atenolol is available as 25 mg, 50 mg and 100 mg tablets, as well as extended release tablets in 25 mg, 50 mg, 100 mg and 200 mg tablets. An injectable form is also supplied as 5 mg/ml.
The typical dose of atenolol for cats is:
- 3 mg/kg by mouth once or twice a day
- Alternative doses used with tablets include:
- ¼ of a 25 mg tablet every day for 3 days, followed by ¼ tablet every 12 hours, or
½ tab in the morning, ¼ to ½ tablet in the evening
Atenolol is a beta blocker that veterinarians prescribe for treatment for certain heart rhythm problems, hypertension, or for hypertrophic cardiomyopathy in cats.
Atenolol belongs to a general class of drugs known as beta-blockers. Other related drugs in this class include Brevibloc® (esmolol), Tenormin® (atenolol) and Inderal® (propranolol).
Atenolol blocks the beta specific receptors and minimizes these effects:
- Artificially increased blood sugar,
- A too-fast heart rate,
- Increased blood pressure
(Basically like the cat is experiencing ‘adrenalin rush’ all the time.)
The effects of metoprolol are especially prominent in the heart, although other organs also can be affected. Typical results include a decreased heart rate, decreased amount of oxygen the heart muscle needs and decreased blood pressure.
Atenolol reduces cardiac output and lowers high blood pressure (systemic hypertension).
Reducing heart rate and strength of heart-muscle contraction can be beneficial to some cats and dogs suffering from a condition called hypertrophic cardiomyopathy, especially when the heart muscle contracts so vigorously it obstructs the path of the blood.
Atenolol is also “cardioprotective,” which means it protects the heart muscle from damage in chronic heart muscle disease. This benefit is sometimes used to treat dogs with dilated cardiomyopathy (heart muscle disease).
Atenolol is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.
Atenolol may cause some animals to become weak due to a slow heart rate or low blood pressure. Rarely, a pet may faint.
Atenolol should be used with caution in animals with congestive heart failure.
Atenolol may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with metoprolol. Such drugs include furosemide, insulin and calcium channel blockers drugs (diltiazem, verapamil, amlodipine).
If a pet collapses while receiving metoprolol tartrate, contact a veterinarian immediately.
How Atenolol Is Supplied
Atenolol is available in 25 mg, 50 mg and 100 mg tablets. Extended release tablets are supplied as 25 mg, 50 mg, 100 mg and 200 mg tablets.
Atenolol tartrate injectable is supplied as 5 mg/ml.
The typical dose of Atenolol administered to cats is 1 mg per pound (2 mg/kg) once daily. The total daily dose in cats is often 2 to 15 mg per cat three times daily. It is very difficult to accurately dose cats therefore Atenolol may need to be compounded.
The typical dose of Atenolol administered to dogs is 6.25 mg to 25 mg per dog two to three times daily. A low dose is generally started and gradually increased every 2 weeks.
The typical dose of Atenolol administered to cats is 1 mg per pound (2 mg/kg) once daily. The total daily dose in cats is often 2 to 15 mg per cat three times daily. It is very difficult to accurately dose cats therefore Atenolol may need to be compounded.
Dosage
Dosage Instructions
The number of preparations available for atenolol for cats allows for a variety of dosage and administration instructions. Oral forms, including tablets, capsules and liquid, will require some cooperation from the cat or the help of a friend.
If using tablets or capsules, place well back on the cat’s tongue. If administering a liquid formulation, expect the cat to spit some liquid out. There’s no need to give them more to make up for that. Many cats prefer the chicken-flavored medicated chew, and accept the oral paste in the mouth. You can give oral medications with or without food, and the therapeutic effect should appear in 1 or 2 hours. Your veterinarian may do lab tests to determine the drug’s effectiveness in your cat. A transdermal gel is given by spreading a stripe between their shoulder blades so they cannot lick it off.
Atenolol for cats is used “off-label,” meaning that the FDA has not put it through its rigorous testing for use in animals like they have for humans. For this reason, it’s essential to follow the dosing and other instructions from your veterinarian precisely, because the drug’s label may differ. The drug stops working within 24 hours of discontinuing it; this time is longer in cats with kidney or liver disease. It is a medication that must be tapered off to avoid a severe shock to the cat’s system.
1. Veterinarians often prescribe Atenolol, a beta-blocker, to treat certain heart rhythm disorders, hypertension, and hypertrophic cardiomyopathy in cats. Atenolol is a member of a broad class of drugs also known as beta-blockers. Other medications in this category include Brevibloc® (esmolol), Tenormin® (atenolol) and Inderal® (propranolol). Atenolol blocks beta receptors, hindering the following effects: artificially raised blood sugar, a too-rapid heart rate, and a higher blood pressure (akin to a perpetual ‘adrenaline rush’ within the feline). Effects can be felt across the body, particularly in the heart, with typical results including a reduced heart rate, less oxygen needed from the heart muscle, and lower blood pressure. Atenolol can also reduce cardiac output and high blood pressure (systemic hypertension), and can be particularly beneficial to cats and dogs experiencing hypertrophic cardiomyopathy in which the heart contracts so intensely that the flow of blood is obstructed. Atenolol can additionally be used as a ‘cardioprotective’ agent, meaning it protects heart muscle from damage in chronic disease – for instance when treating dogs with dilated cardiomyopathy.
This prescription-only medication can weaken animals due to a slower heart rate and low blood pressure – fainting is a rarely observed side effect. Atenolol should be used cautiously in animals with congestive heart failure and can interact with certain other medical drugs, such as furosemide, insulin, or calcium channel blockers (diltiazem, verapamil, and amlodipine). In the event that a pet collapses while taking Atenolol, it’s imperative to contact a veterinarian immediately.
Atenolol is available in tablet form (25 mg, 50 mg, and 100 mg) as well as extended release tablets (25 mg, 50 mg, 100 mg, and 200 mg). A liquid solution (Atenolol tartrate injectable) is supplied as 5 mg/ml and the typical dose for cats amounts to 1 mg per pound (2 mg/kg) once daily, with a maximum daily dose of 15 mg/cat. Dogs often receive 6.25 to 25 mg two to three times daily, gradually increasing the dosage every two weeks. Dosing cats accurately may require soaking Atenolol into compounded drugs.
Feline hypertrophic cardiomyopathy_ an update
Feline Hypertrophic Cardiomyopathy_ An Update12
Management of Feline Cardiomyopathies – WALTHAMOSU2002 – VIN
Treatment of Feline Hypertrophic Cardiomyopathy – Lost Dreams – WSAVA 2014 Congress – VIN
