Hydralazine For Dogs: Uses, Dosage, & Side Effects

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Hydralazine is a drug that treats high blood pressure in dogs by opening up the blood vessels and reducing stress on the heart and arteries. It can also be used to treat congestive heart failure in dogs. Hydralazine works by inhibiting the movement of calcium, which is necessary for muscles to contract. This forces the smooth muscles in the arteries to relax and lowers blood pressure. If your veterinarian prescribes hydralazine for your dog, you should follow instructions closely, as improper use can result in conditions like hypotenstion (low blood pressure), water retention, or other problems. Here is what you should know about the uses, dosage, and side effects of hydralazine in dogs.

Uses Of Hydralazine For Dogs

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Hydralazine is primarily used to treat hypertension or high blood pressure in dogs. It may also aid in the treatment of congestive heart failure, often alongside other medications, particularly heart failure associated with the condition mitral valve endocardiosis.

Dosage Of Hydralazine For Dogs

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The usual dosage of hydralazine for dogs is 1.1 to 1.76 mg per pound given twice a day orally. The medication usually comes in tablets that can be 10 mg, 25 mg, 50 mg, or 100 mg. You should always follow your veterinarian’s instructions for dosage. They may make adjustments based on your dog’s response to the drug. Hydralazine also comes in an injectable form, and your veterinarian will give you guidelines on how this is administered.

Side Effects Of Hydralazine In Dogs

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The most common side effects of hydralazine in dogs include vomiting, diarrhea, loss of appetite, lethargy, conjunctivitis, constipation, or water retention. In some cases, hydralazine can cause the opposite of high blood pressure, which is hypotension, a condition where blood pressure gets too low. This can cause weakness and an increase in heart rate. You should consult your veterinarian if you see any concerning side effects. Your vet may be able to alter the dosage or find a different course of treatment. A vet may also prescribe a diuretic to relieve water retention.

Hydralazine shouldn’t be used in dogs that already have low blood pressure. You should inform your vet of any other medical conditions your dog suffers from, especially liver disease, kidney disease, or autoimmune disease. You should also tell your vet about any other medications your dog takes, including over-the-counter medications, as these can react poorly with hydralazine. As with all medications, there is a risk of allergic reaction that could lead to anaphylaxis. If you see the signs of an allergic reaction to hydralazine, contact your veterinarian immediately.

Has your dog ever been treated with hydralazine? Was it effective? Let us know in the comments below!