Canine Cognitive Dysfunction Syndrome

Anipryl is made by Pfizer for the treatment of Canine Cognitive Dysfunction Syndrome or CDS. As dogs age there are chemical and physical changes in the brain. Signs of dogs with CDS can include signs of confusion or other behavioral changes that are not part of normal aging. Owners of dogs with CDS often describe their dog as less responsive, confused or forgetful. This article is important if your dog is over eight years old.

Anipryl is the veterinary trade name for a drug called selegiline hydrochloride, also known as L-deprenyl. It is used in humans for treatment of Parkinson's Disease, Alzheimer's Disease, and Cushing's Disease. The drug is approved by the FDA for use in dogs for treatment of Pituitary Dependent Hyperadrenocorticism (PDH) also known as Cushing's Disease and Canine Cognitive Dysfunction.

Signs of CDS

Appear lost in the house or yard

Don’t recognize owners

Don’t respond to name

Doesn’t appear interested in affecton or petting

More accidents inside the house

Personality changes

Above all, Pfizer says to resist the urge to tell yourself that your dog is “just getting old.” With your help, your veterinarian can determine if the changes in your dog are associated with canine Cognitive Dysfunction Syndrome.To arrive at a diagnosis of CDS your vet should to a general physical exam to rule out any physical or medical problems that could cause abnormal behavior.

Does it work?

In one study at the University of California-Davis, 62% of 11- to 16-year-old dogs showed signs in at least one category of CDS.1,2 In a pet owner survey, nearly half of dogs age 8 and older showed at least one sign associated with CDS.Pfizer reports in studies that pet owners reported that 69% to 75% of dogs improved in at least one clinical sign after one month of Anipryl therapy. Because CDS is a syndrome (a collection of signs), no two dogs will show exactly the same signs. Response to Anipryl may vary from dog to dog.


CDS: The recommended dosage for oral administration for the control of clinical signs associated withCDS is 0.5–1.0 mg/kg once daily, preferably administered in the morning.

After 4 weeks of treatment, dogs treated showed significant improvement

AvailabilityHOW SUPPLIED: Five tablet strengths are available in blister-packs of 30 tablets each: 2 mg, 5 mg, 10 mg,15 mg, and 30 mg. Each box contains 1 blister pack (30 tablets).

Anipryl Side Effects

Common side effects

noted in field trials include:

Dog Vomiting

Dog Diarrhea



Dog Neurologic Problems


Pathogenesis of CDSThe pathogenesis of the development of clinical signs associated with cognitive decline is considered to be partly a result of a decrease in the level of catecholamines in the CNS and deficiencies in neurotransmission. There is evidence which points to hypothalamic dopamine deficiency playing a role in the pathogenesis of pituitary dependent hyperadrenocorticism in the dog.

It is available by prescription onlyMost information taken from Phizer website. Visit their website for a free 30 day trial.

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