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Priapism in Dogs and Cats

ByAutumn P. Davidson, DVM, MS, DACVIM, Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis
Reviewed/Revised Apr 2025

Priapism is a persistent erection without sexual stimulation. Partial paraphimosis can also result.

Priapism can be caused by myelopathy, drugs, vascular abnormalities, penile masses, trauma, or castration (in cats), or it can be idiopathic. Nonischemic priapism is more common than ischemic priapism in dogs and cats.

Diagnosis is by physical examination (see dog and cat priapism images) and is confirmed with ultrasonography of the penis.

When priapism is nonischemic and no primary cause is identified, treatment with medication can be attempted. Several systemic medications are of potential benefit, although few controlled data exist regarding the efficacy of systemic drug therapy. One of the following drugs should be tried:

  • gabapentin: in dogs, 10–20 mg/kg, PO, every 8 hours to effect; in cats, 10 mg/kg, PO, every 8 hours to effect

  • terbutaline: in dogs, 1.25–5 mg/dog, every 8–24 hours to effect; in cats, 0.625 mg/cat, PO, every 12–24 hours to effect

  • pseudoephedrine (extralabel use): in dogs, 1.5 mg/kg, PO, every 8–12 hours to effect; in cats, 1 mg/kg, PO, every 8–12 hours to effect

If detumescence is not achieved after several days of treatment with one drug, switching to another drug may work.

When priapism is ischemic in cats, penile amputation and perineal urethrostomy may be indicated.

A type of surgical treatment in which several small incisions are made in the tunica albuginea of the penile corpora cavernosa and in some other parts of the corpora cavernosa, followed by irrigation with heparinized saline solution (0.9% NaCl), has reportedly had some success. Sutures are then placed to close the skin; the tunica albuginea is not closed.

Pearls & Pitfalls

  • Castration is not helpful for dogs and cats with priapism, because priapism is not testosterone mediated.

Nonischemic feline priapism can respond to medical management, as in dogs.

In both dogs and cats, castration is not helpful, because priapism is not testosterone mediated.

If necrosis or gangrene due to priapism is severe, amputation of the penis and prepuce and urethrostomy might be necessary.

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