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Proin—Phenylpropanolamine—for Dogs

Proin—a brand of phenylpropanolamine for dogs—is a popular prescription medication for urinary incontinence. While phenylpropanolamine—or PPA as it's sometimes known—was designed as a decongestant for humans, it is now sold in the United States for veterinary use only. The drug works by stimulating receptors on smooth muscles around the urethral sphincter to strengthen muscle fibers that can help your dog control their bladder. If your pup has trouble holding their pee due to a condition like urethral sphincter hypotonus, your veterinarian may prescribe Proin to help.

Because of its potential drug interactions and side effects, Proin should only be given to your dog under the direction of a vet. The medication may be an effective and simple solution for resolving your dog's bladder control issues. If your pet needs additional support for urinary issues, Petco carries a number of over-the-counter solutions to help support their urinary health. 

Proin is available from Petco in three different strengths. All require a prescription from your veterinarian. Shop for Proin on our site, and we'll take care of confirming veterinary authorization before delivering your medication straight to your door. If your pup regularly takes phenylpropanolamine for urinary incontinence, you can also choose Repeat Delivery at checkout for further savings.

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How much Proin can my dog take?

Proin (phenylpropanolamine hydrochloride) comes in bottles of 60 or 180 chewable tablets in  25, 50 and 75 milligram doses. An extended-release tablet called Proin ER is also available, and other brands of phenylpropanolamine come in liquid form. The tablets are typically given with food.

Your veterinarian will tell you the recommended dosage for your pup's specific size and medical needs. Dosage for dog bladder control is typically calculated per pound of a dog's weight. In general, vets prescribe phenylpropanolamine for dogs in the range of roughly .5 to 1.0 milligrams per pound, and your vet may recommend giving more than one dose per day. Doses for Proin ER are a bit higher. If you miss a dose, consult your veterinarian for guidance.

Even though veterinary use of phenylpropanolamine rarely results in side effects, there have been instances of dogs getting ahold of it, chewing through the plastic bottle and overdosing. Be sure to store your medication bottle somewhere out of chomping range so your dog doesn't mistake it for a bottle of treats.

The side effects of Proin in pregnant and nursing dogs have not been extensively studied. It should only be given if directed by your veterinarian.

How quickly does Proin work in dogs?

Proin is intended to improve incontinence and "dribbling" in dogs but will not cure it. Once it has been administered, urinary incontinence in dogs usually begins to improve in an hour or two. The medication typically remains in the body for four to seven hours. However, when you first start your dog's regimen of Proin, it may take a few days before you see an effect on your dog's incontinence.

Phenylpropanolamine is a short-acting medication, which means that it can take effect quickly, but it does not stay in a dog's system for long. Therefore, many types of phenylpropanolamine need to be administered several times throughout the day according to your veterinarian's instructions. An exception is Proin ER, an extended-release form of the drug that should only be given once every 24 hours. Many dogs with urethral sphincter hypotonus can suffer from urinary incontinence during the night. Therefore, it is often recommended that a larger dose of phenylpropanolamine be given at bedtime to last as long as your dog sleeps.

Remember that there is no one-size-fits-all dose of the dog incontinence medicine Proin. Your veterinarian will recommend the correct form of phenylpropanolamine (liquid, chewable or extended-release) that is ideal for your pup's weight and condition, as well as the dose and the frequency in which it should be administered. If you are following your vet's instructions and your dog is still having trouble with urinary incontinence, consult your veterinarian about the possibility of adjusting your dog's incontinence medicine.

What are the potential side effects of Proin?

Like with any medication, phenylpropanolamine may cause side effects ranging from mild to severe. If your vet recommends Proin for your dog, side effects may include:

  • Loss of appetite
  • Vomiting and diarrhea
  • Heavy drooling
  • Restlessness and irritability
  • Increased blood pressure or heart rate
  • Seizures
  • Difficulty urinating

If your dog is allergic to phenylpropanolamine, symptoms of an allergic reaction can include:

  • Facial swelling
  • Hives
  • Itching or scratching
  • Sudden onset of diarrhea or vomiting
  • Shock
  • Seizures
  • Pale gums and cold limbs
  • Coma

You should also be aware of the symptoms of overdose in case your dog gets into the bottle unbeknownst to you. If your dog experiences an overdose in response to phenylpropanolamine, they may exhibit any of the following signs:

  • Loss of appetite
  • Weakness
  • Very rapid heart rate
  • Increased blood pressure
  • Swelling
  • Trouble breathing
  • Collapse
  • Difficulty walking
  • Convulsions

If you notice any of these side effects or signs of a drug allergy while your dog is taking Proin, contact your veterinarian immediately.

There are some medications and pre-existing medical conditions that could prevent your dog from being able to take Proin. Dogs with liver disease or glaucoma, for example, may need to stay away from phenylpropanolamine, and it's important to proceed with caution if your dog is taking monoamine oxidase inhibitors (MAOIs) or nonsteroidal anti-inflammatory drugs (NSAIDs) or is currently wearing a tick collar. This medication is also not recommended for use in dogs who are taking xylazine, dexmedetomidine, selegiline or amitraz. Let your vet know what drugs or dog vitamins and supplements your pup is taking before starting a Proin regimen.

Do Proin side effects go away?

Phenylpropanolamine for dogs can cause some side effects that, while typically not severe, can make your dog uncomfortable. You may be frustrated if you feel you have to choose between your dog's urinary tract health and overall wellbeing. However, just because there are potential side effects, that doesn't necessarily mean your dog can't take phenylpropanolamine. It may simply be that the frequency or dosage of your dog's medication needs to be adjusted. If you notice that your dog has diarrhea after taking Proin, for instance, your vet may recommend a lower dose.

The good news is that since phenylpropanolamine leaves your dog's system quickly, uncomfortable side effects may clear up in as little as hours of stopping the medication.

Does Proin make dogs thirsty?

Phenylpropanolamine tablets may cause an increase in thirst. It might seem counterintuitive to give extra water to a dog who is currently experiencing urinary incontinence. Still, if your dog is extra thirsty they'll be uncomfortable if they're not adequately hydrated. If Proin is working correctly, your dog should be able to hold their urine even if they're drinking a little more water than usual. It's acceptable to go ahead and fill your dog's water bowl if they seem a bit thirsty while on phenylpropanolamine.

Can Proin make my dog aggressive?

Although it’s unusual, aggression can occur as a result of other side effects. Proin can occasionally make dogs feel irritable, anxious or antsy, which could lead to your dog exhibiting a crabby mood or short temper. Aggression might be one of the manifestations of these mood and behavior changes. If your pup seems on edge or aggressive while on Proin, you may want to consider browsing Petco's selection of dog calming aids to help put them at ease. Consult your veterinarian to report the behavior or before adding any new supplements to your dog's diet while they're on dog incontinence medicine.


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Proin ER

Reviewed by Dr. Whitney Miller, DVM, MBA, DACVPM

As Petco’s Chief Veterinarian, Dr. Miller is the lead veterinary subject matter expert, overseeing the company’s standards of excellence in animal care and welfare, growth in pet services and much more. Dr. Miller leads Petco’s medical team, supporting over 200 full-service hospitals and mobile vaccination clinics operating in over 1,000 Petco Pet Care Centers nationwide