1. Drug name:

Phenylpropanolamine (PPA)

2. Common Names or Brand Names:

Proin, Propalin, Cystolamine, Uricon, Uriflex-PT

3. How Dispensed:

In the US, Proin is a prescription and veterinary use only medication. It is no longer produced for human use.

Be sure to follow your veterinarian’s instructions for administration and cautions as these will be tailored to your specific pet.

4. Forms:

Liquid or tablet (can be chewable tablet as well) of 25mg, 50mg and 75mg

It acts fairly quickly and takes effect within 1-2 hours.

5. Drug Type/Class:

Sympathomimetic – imitates the sympathetic or “Fight or Flight” system

6. Uses in Cats and Dogs:

Used to treat urinary incontinence due to poor muscle tone in the urethral sphincter

7. How it Works:

Proin acts on receptors that cause typical “Fight or Flight” “fear” nervous system response, causing the bladder outlet sphincter to tighten, increasing heart rate and blood pressure

8. Side Effects and/or Signs of Overdose:

• Vomiting
• Diarrhea
• Lack of appetite
• Increased thirst
• Restlessness
• Irritability
• Difficulty urinating

Serious Side Effects:

• Seizures
• Collapse
• Stroke-like signs (like not being able to walk)

9. Drug Interactions:

• Aspirin
• Isoflurane/Desflurane/Sevolurane (inhalant anesthetics)
• monoamine oxidase inhibitors (MAOIs) – social phobia treatments
• Non-steroidal anti-inflammatory drugs (NSAIDs) – like Carprofen, Rimadyl
• Reserpine
• other sympathomimetics
• tricyclic antidepressants

10. Cautionary Statements:

• Blood pressure should be monitored frequently when your pet first starts taking phenylpropanolamine, and then at least twice per year.
• Should not be used in pregnant pets or in pets allergic to it
• Should be used cautiously in pets with glaucoma, seizures, enlarged prostate, elevated thyroid hormone, diabetes mellitus, heart or vessel disorders, kidney disease, or high blood pressure
• Should be used cautiously in nursing pets, as safety has not been studied
• Provide access to fresh water at all times
• Measure the liquid form carefully
• It is often best to give with some food to avoid stomach upset
• If there is incontinence at night, the larger dose (if there is one) should be given before bedtime at night

Additional Information:

Since bladder control comes from the nerves in the pelvic area, some pets can be helped by veterinary chiropractic adjustment without the need for worrisome side effects and monitoring. See our article about Veterinary Chiropractic as well as Acupuncture.

Read more:

Why does my pet need a urinalysis?

Urinary Tract Infection (UTI) in Dogs

Bladder Stones in Dogs

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