Proin for dogs: incontinence medicine uses and side effects

Proin is a prescription medicine for dogs that leak urine without knowing it, usually while resting or asleep. Its active ingredient, phenylpropanolamine, tightens the muscle that holds the bladder outlet closed. It works for most dogs whose leaking is caused by a weak outlet, often within days, and it is usually given for life.

This site does not give doses for any medicine. The amount of Proin depends on your dog's weight, age, blood pressure, kidneys, heart and other medicines, and only the prescribing vet can set it.

What Proin is used for in dogs

The bladder is held shut by a ring of muscle around the urethra, the tube that carries urine out. In some dogs that muscle loses tone. Urine then seeps out when the dog is relaxed, and the usual sign is a wet patch where they were lying. The dog is not misbehaving and often does not notice.

This kind of leaking is most common in middle-aged and older spayed females, particularly larger dogs. It also happens in males, who tend to respond less well to the medicine.

Phenylpropanolamine acts on the nerve receptors in that muscle and makes it grip more firmly. It does not treat any other cause of accidents in the house, which is why the vet tests before prescribing.

What the vet rules out first

• Urinary tract infection and bladder stones
• Conditions that make a dog drink and urinate far more, such as kidney disease, diabetes and Cushing's disease
• Spinal or nerve problems that affect bladder control
• Dementia, where the dog forgets house training but is awake and aware when urinating

Expect a urine test at least, and usually blood tests and a blood pressure reading in an older dog.

How long does it take for Proin to work?

Many dogs leak less within the first few days, and some owners find a dry bed after a day or two. Vets usually judge the result properly after a few weeks and adjust from there.

It only works while it is being given. If it is stopped, the leaking generally returns. In some dogs the effect fades over months or years, and the vet may then change the plan or add a second medicine.

Proin and Proin ER: the difference

Both contain the same drug. Breaking or crushing an extended-release tablet can release the whole amount at once, so tell the vet if your dog chews tablets instead of swallowing them. The two are not swapped one for one. A change between them is the vet's decision.

Proin side effects

Phenylpropanolamine stimulates the same system that adrenaline does, and the side effects follow from that. Those reported include:

• Vomiting or diarrhea
• Loss of appetite and weight loss
• Restlessness, anxiety, irritability or trouble settling
• Raised blood pressure
• A fast heart rate or panting
• Increased thirst
• Tiredness
• Protein in the urine, found on testing

Raised blood pressure is the one that matters most, because you cannot see it at home. Sustained high blood pressure can damage the kidneys, eyes, heart and brain. Rare serious events, including seizures, collapse and stroke-like episodes, have been reported.

Side effects of Proin in older dogs

Older dogs are the ones most likely to need Proin and the ones most likely to have a reason for caution. Vets are careful, or choose something else, when a dog has:

• Heart disease. A faster heart rate and higher pressure add to the heart's workload.
• Kidney disease. The kidneys are damaged by high blood pressure and often cause it.
• Glaucoma. The drug can affect pressure inside the eye.
• Existing high blood pressure, or conditions that raise it, such as Cushing's disease and diabetes.
• Liver disease.

Expect a blood pressure check before starting, again soon after, and at regular rechecks, along with blood and urine tests. A dog who was fine on Proin at eight may not be at thirteen, so the checks continue for as long as the medicine does.

Is Proin safe for dogs?

It is an approved veterinary medicine and many dogs take it for years without trouble. It is not risk-free, and whether it is a reasonable choice for your dog depends on their heart, kidneys, eyes and blood pressure. That judgment belongs to the vet who has examined them.

Give the vet a full list of what your dog takes. Vets watch for interactions with selegiline (used for dementia), amitraz tick collars and dips, some antidepressants and behavior medicines, and aspirin and some other anti-inflammatory pain relievers. Never give human painkillers: ibuprofen, naproxen, acetaminophen (paracetamol) and aspirin can seriously harm or kill dogs. Human cold and allergy products that contain decongestants act in a similar way and are dangerous to dogs. Never use one as a stand-in.

Missed dose, double dose and overdose

If you miss a dose, call the clinic and ask what to do. Do not give two together. The likely result of one missed dose is a wet bed.

Overdose is a real risk with this medicine. The chewable tablets are flavored, and dogs have chewed through closed containers to eat them. Too much can cause agitation, a racing or very slow heart, dangerously high blood pressure, tremors and seizures. If your dog has had extra, or another pet has eaten some, call your vet, an emergency clinic or an animal poison control line right away. Store it in a closed cupboard, not on a counter or in a bag.

Proin alternatives

If Proin does not suit your dog or does not work well enough, the vet has other options. Each has its own risks, and each needs a prescription or a referral.

• Estriol. An estrogen medicine approved for spayed female dogs. It improves the tone of the tissues around the bladder outlet and is often chosen when blood pressure is a concern.
• Other estrogens. An older one, diethylstilbestrol, is still used in some dogs. Estrogens can have serious side effects if the amount is wrong.
• A combination. Some dogs do best on Proin and an estrogen together.
• Procedures. Specialists can inject a bulking material around the urethra or place a small adjustable cuff. These are for dogs who do not respond to medicine.

Supplements sold for bladder control have little good evidence behind them and are not regulated like medicines. Ask the vet before adding one.

Management matters with or without medicine: washable bedding, waterproof covers, a last trip outside before bed, and keeping the skin clean and dry to prevent urine scald. See solutions for senior dog incontinence for the practical side.

Call the vet today if

• Your dog has eaten more Proin than prescribed. Treat this as an emergency.
• Your dog collapses, has a seizure, seems suddenly blind, tilts their head or cannot walk straight.
• You notice marked restlessness, panting, trembling or a racing heart after a dose.
• Your dog stops eating or vomits repeatedly.
• Your dog strains to urinate, passes only drops or has blood in the urine. Being unable to pass urine is an emergency.
• Leaking returns or gets worse on the medicine, or your dog is drinking much more than usual.

Questions to ask the vet

• What tests show the leaking is from a weak bladder outlet and not something else?
• What was my dog's blood pressure, and when will it be checked again?
• Do my dog's heart, kidneys or eyes change the choice of medicine?
• Regular tablets or extended-release, and with or without food?
• Would estriol be an option for my dog?
• What should I do about a missed dose?

This page is general educational information about Proin (phenylpropanolamine), not veterinary advice, and it gives no doses. Whether this medicine or an alternative is right for your dog, and how it is given and monitored, are decisions for your own veterinarian. Do not start, stop or change it without asking them, and contact a vet or an animal poison control line immediately if your dog gets more than prescribed.