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(phenylpropanolamine hydrochloride)

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25 mg Tablet;  
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50 mg Tablet;  
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180 count Proin JPG Image  Proin PowerPoint Image
75 mg Tablet;  
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180 count Proin JPG Image  Proin PowerPoint Image

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PROIN® (phenylpropanolamine hydrochloride) is FDA approved for control of canine urinary incontinence due to urethral sphincter hypotonus. In an FDA approved 28 day clinical trial PROIN reduced mean urinary accidents per week in female dogs by 82%.1 In the second part of the clinical field study (180 days), PROIN achieved 98.1% owner satisifaction for the control of urinary incontinence.2

A 28-day placebo-controlled clinical study was conducted in 21 study sites across the U.S. The study included 184 dogs with urinary incontinence due to sphincter hypotonus of which 127 dogs (100 female, 27 male) were evaluated for effectiveness. Dogs were randomly assigned either to receive 2 mg/kg PROIN (123 dogs) or a placebo (61 dogs) administered orally twice daily for 28 days. PROIN administered at 2 mg/kg orally twice a day was effective for the control of urinary incontinence based on a decrease in urinary accidents per week as compared to the placebo. Changes to hematology and serum chemistry were not considered clinically significant or related to treatment. The most commonly reported side effects were: emesis, hypertension, anorexia, weight loss, proteinuria, and behavioral changes.

In a margin of safety study, phenylpropanolamine hydrochloride (PPA) was administered to dogs twice daily at 1X, 3X or 5X the recommended dose (2 mg/kg) for 182 days. This study demonstrated the safety of phenylpropanolamine administered to dogs at 2, 6 and 10 mg/kg twice daily for 6 months. The most pronounced effects of treatment were a dose-dependent increase in blood pressure, and a dose dependent decrease in heart rate. There were no findings in ophthalmic examinations or histologic evaluation of tissues collected at necropsy to indicate target organ damage that would be caused by chronic hypertension. A decline in body weight and condition was noted in both treated and untreated females. Temporary elevations of platelet count and serum ALT were observed in treated dogs.

Why Proin?
  • Proven safe and effective
  • Multiple strength options
  • Contains no beef or beef by products
  • Chewable scored tablets
  • Liver flavored

IMPORTANT SAFETY INFORMATION: For oral use in dogs only. Not for human use. Keep out of reach of children. If accidentally ingested by humans, contact a physician immediately.

The most commonly reported side effects were vomiting, loss of appetite, diarrhea, excessive salivation, agitation, tiredness, vocalization, confusion, increased water consumption, weight loss, weakness, fever, panting, and reversible changes in skin color (flushing or bright pink). Abnormal gait, seizures or tremors, as well as liver enzyme elevations, kidney failure, blood in urine and urine retention have been reported. In some cases death, including euthanasia has been reported. Sudden death was sometimes preceded by vocalization or collapse.

Instances of dogs chewing through closed vials of PROIN and eating the vial contents have been reported, in some cases resulting in overdose. Keep the product in a secured storage area out of the reach of pets in order to prevent accidental ingestion or overdose, as dogs may willingly consume more than the recommended dosage of PROIN Chewable tablets. Contact your veterinarian immediately if the dog ingests more tablets than prescribed or if other pets ingest PROIN Chewable tablets.

PROIN may cause elevated blood pressure and should be used with caution in dogs with pre-existing heart disease, high blood pressure, liver disease, kidney insufficiency, diabetes, glaucoma, and other conditions associated with high blood pressure.

The safe use of PROIN in dogs used for breeding purposes, during pregnancy or in lactating bitches, has not been evaluated. Contact your veterinarian if you notice restlessness or irritability, loss of appetite, the incontinence persists or worsens or any other unusual signs. See prescribing information for complete details regarding adverse events, warning and precautions or visit

1Multi-center Clinical Evalutation of Phenylpropanolamine Chewable Tablets for the Control of Urinary Incontinence in Dogs due to Sphincter Hypotonus, Pegasus Laboratories, Incorporated-CL-001 2010.

2Clinical Evaluation of the Long Term Effectiveness and Safety of Phenylpropanolamine Chewable Tablets for the Control of Urinary Incontinence in Dogs, Pegasus Laboratories, Incorporated-CL-002 2010.

CAUTION:Federal law restricts this drug to be used by or on the order of a licensed veterinarian. See reverse for full directions for use.




For the control of urinary incontinence due to urethral sphincter hypotonus in dogs.

Active Ingredients

Phenylpropanolamine hydrochloride