Question 1

My house-trained dog is having accidents and wetting the bed - is this the furosemide?

Accepted Answer

Almost certainly, and you're not alone - this is the single most common furosemide complaint among owners of heart-failure dogs. The drug produces large volumes of urine on a schedule your dog can't always control, especially overnight. Practical strategies owners use: a final bathroom trip as late as possible, washable waterproof bedding or covers, and more frequent daytime outings. Some vets adjust the timing of doses so the peak effect doesn't land overnight - but never shift dose times or skip a dose yourself to avoid accidents; ask your vet. Punishing the dog is pointless: this is pharmacology, not a training failure.

Question 2

My dog is drinking and urinating constantly - is this normal?

Accepted Answer

Yes - intense thirst and increased urination are the expected effects; the medication is removing excess fluid and your dog is replacing water losses. Make sure your dog always has access to fresh water and gets frequent bathroom breaks. If urination seems truly excessive, your dog seems weak or dehydrated, or is losing weight rapidly, contact your vet.

Question 3

Should I restrict water intake?

Accepted Answer

No - never restrict water for a dog on furosemide unless specifically instructed by your veterinarian. The medication causes fluid loss and your dog needs to stay hydrated. Restricting water on a diuretic can cause serious kidney damage. Always provide free access to fresh water, including overnight and when you're out.

Question 4

What bloodwork does my dog need on furosemide?

Accepted Answer

Kidney values (BUN, creatinine) and electrolytes (especially potassium) are the key numbers. Vets typically check them before starting, within a week or two of starting or any dose increase, and then at regular intervals for as long as your dog is on the drug. Furosemide makes the kidneys work hard, and dose adjustments are often driven by these results - it's one of the most important monitoring routines in heart-failure care.

Question 5

How do I know if the furosemide dose needs adjusting?

Accepted Answer

Monitor your dog's resting respiratory rate (breaths per minute while sleeping). Normal is under 30. If it consistently rises above 30–40, it may indicate fluid is building up and the dose needs increasing. Track this daily - it's one of the most valuable things you can do at home. Report the trend to your vet; never adjust the dose yourself.

Question 6

Can furosemide be stopped or reduced once the fluid is under control?

Accepted Answer

Only your veterinarian can make that call. Some dogs are gradually stepped down to the lowest effective dose once congestive heart failure is stabilized, but stopping a diuretic in a heart-failure dog without guidance can let fluid rebuild in the lungs within days. If side effects like accidents or thirst are wearing on your household, raise it with your vet - dose timing and adjunct medications can often be adjusted. Never stop heart medications on your own.

Lasix (Furosemide)

How it works

Common dosage

Side effects to watch for

Drug interactions

Frequently asked questions

Other DCM medications