{"id":628691,"date":"2024-06-24T19:26:24","date_gmt":"2024-06-24T23:26:24","guid":{"rendered":"https:\/\/www.singlecare.com\/blog\/?p=628691"},"modified":"2025-06-11T10:14:19","modified_gmt":"2025-06-11T14:14:19","slug":"spironolactone-for-dogs","status":"publish","type":"post","link":"https:\/\/www.singlecare.com\/blog\/spironolactone-for-dogs\/","title":{"rendered":"Spironolactone for dogs: Uses, dosage, and safety"},"content":{"rendered":"

Spironolactone<\/span><\/a> (brand name: Aldactone) is a <\/span>potassium-sparing diuretic<\/span><\/a> that increases water and sodium excretion through urine. Veterinarians never use spironolactone by itself but always combine it with other medications. Pet parents can expect to give their dog one dose daily, either as a tablet or a specially prepared liquid. In some cases, spironolactone is a long-term or even lifelong treatment.\u00a0<\/span><\/p>\n

RELATED: <\/b>Save up to 80% on spironolactone<\/b><\/a><\/p>\n

What is spironolactone used for in dogs?<\/span><\/h2>\n

In dogs, spironolactone is useful in treating <\/span>congestive heart failure<\/span><\/a> and other cardiovascular conditions when other drugs are not working well or causing potassium levels to fall too low. Veterinarians also use it for other purposes, including treating fluid buildup in the belly (ascites), treating <\/span>high blood pressure<\/span><\/a>, and reducing fluid buildup when the kidneys are having filtering problems. For all these conditions, veterinarians only use it with other medications.<\/span><\/p>\n

Congestive heart failure (CHF)<\/span><\/h3>\n

Heart failure describes any situation in which the heart cannot pump enough blood to the rest of the body. In dogs, as in humans, <\/span>there are many causes<\/span><\/a> of heart failure, including genetidcs, valve disease, fluid buildup around the heart, \u201cback-leak\u201d of the blood, high blood pressure, pulmonary hypertension, and heart structure abnormalities. Valve disease is the primary cause of heart failure in dogs, accounting for about <\/span>80%<\/span><\/a> of cases.<\/span><\/p>\n

Veterinarians choose medications based on the cause. Standard treatment of congestive heart failure includes diuretics such as <\/span>furosemide<\/span><\/a> to reduce fluids, drugs that dilate blood vessels such as <\/span>ACE inhibitors<\/span><\/a> or <\/span>pimobendan<\/span><\/a>, and drugs that change the way the heart beats, such as <\/span>digoxin<\/span><\/a>, <\/span>beta blockers<\/span><\/a>, and <\/span>calcium channel blockers<\/span><\/a>.<\/span><\/p>\n

Veterinarians use spironolactone if diuretic treatment does not work well or the diuretics being used deplete too much potassium from the system. Spironolactone does not seem to <\/span>have any other benefit<\/span><\/a> in treating heart failure in dogs other than maintaining normal potassium levels.<\/span><\/p>\n

Ascites (abdominal fluid buildup)<\/span><\/h3>\n

Veterinarians call fluid buildup in the abdomen \u201cascites.\u201d Ascites is a serious and potentially life-threatening condition caused by blocked liver veins. Blood vessel problems have several <\/span>possible causes<\/span><\/a>, including blood clots, strictures, swelling, compression, scarring, tumors, or any other problem that restricts blood flow through these veins. These blood vessel problems are often a <\/span>consequence<\/span><\/a> of other conditions like heart failure, liver failure, or heart disease.\u00a0<\/span><\/p>\n

For ascites, veterinarians treat the cause. They only use diuretics to reduce the fluid building up in the abdomen. Spironolactone is added to the treatment to both reduce fluid buildup and keep potassium at normal levels.\u00a0<\/span><\/p>\n

High blood pressure<\/span><\/h3>\n

A dog with systemic hypertension has blood pressures in the arteries that are high enough to damage blood vessels and organs over time. High blood pressure is common among people. The <\/span>CDC<\/span><\/a> reports that 48% of adults have high blood pressure. Most cases involve primary hypertension, that is, high blood pressure that isn\u2019t caused by any other medical condition.\u00a0<\/span><\/p>\n

It\u2019s not the same for dogs. High blood pressure is relatively uncommon in dogs. Most dogs are diagnosed with secondary hypertension, meaning high blood pressure that has an <\/span>identifiable cause<\/span><\/a>, such as kidney disease, adrenal gland problems, or other medical conditions.\u00a0<\/span><\/p>\n

When a dog has high blood pressure, veterinarians usually treat the cause. To bring blood pressure back to normal, veterinarians use many of the same drugs doctors use in people, including ACE inhibitors such as <\/span>benazepril<\/span><\/a>, <\/span>angiotensin-II receptor blockers<\/span><\/a> (ARBs), <\/span>beta blockers<\/span><\/a>, <\/span>calcium channel blockers<\/span><\/a>, and <\/span>diuretics<\/span><\/a>. Spironolactone is not the first drug a veterinarian will use. Instead, it\u2019s added if other drugs aren\u2019t working or there\u2019s a problem with low potassium levels.\u00a0<\/span><\/p>\n

RELATED: <\/b>How to manage high blood pressure in dogs<\/b><\/a><\/p>\n

Glomerular disease<\/span><\/h3>\n

Glomerular disease is a type of kidney disease. The glomeruli are groups of small tubules in the kidneys. When blood passes through these small tubules, substances the body doesn\u2019t need\u2014like water and waste\u2014pass through them into the urine. Stuff the body does need\u2014like blood cells and proteins\u2014are filtered so they don\u2019t pass out of the body. Glomerular disease describes what happens when that process doesn\u2019t work, so the urine gets foamy or discolored, and fluid builds up in the body.\u00a0<\/span><\/p>\n

Glomerular disease in dogs is always a result of medical conditions like diabetes, infection, drugs, autoimmune disorders, or other diseases. The veterinarian will primarily address these other causes. To reduce swelling and fluid buildup, veterinarians use diuretics to increase water loss. If potassium levels get low, spironolactone is added to diuretic treatment.\u00a0<\/span><\/p>\n

Is spironolactone safe for dogs?<\/span><\/h2>\n

Veterinarians consider spironolactone safe in dogs as either a backup or adjunct treatment. Because spironolactone prevents the kidneys from eliminating potassium, it is not safe to give to dogs with high potassium levels. Some medical conditions, such as <\/span>diabetes<\/span><\/a>, Addison\u2019s disease, and kidney problems, cause high potassium, so spironolactone is contraindicated in dogs with those conditions. Veterinarians use spironolactone cautiously in dogs with liver disease or dysfunction.<\/span><\/p>\n

Side effects of Spironolactone in dogs<\/span><\/h3>\n

The most common side effects of spironolactone in dogs are:<\/span><\/p>\n