Diagnosing priapism 

Priapism can usually be diagnosed by your GP examining your penis and asking questions about your symptoms and medical history.

For example, you may be asked:

  • how long your penis has been erect
  • whether your penis is painful or tender
  • whether you have had previous episodes of priapism and how they were treated
  • whether you have a known blood disorder, such as sickle cell anaemia
  • whether you have recently taken recreational drugs, such as cocaine or ecstasy

You may also be asked whether you have recently injured your penis or perineum (the area in between your genitals and anus). This injury may occur up to two weeks before the development of the long-lasting erection.

Blood tests

Blood tests may be needed to find out what is causing your priapism. These can help detect underlying problems with your blood, such as anaemia (a lack of red blood cells), or unusually high numbers of white blood cells, which could be a sign of leukaemia.

Blood tests can also measure the levels of oxygen and carbon dioxide in your blood. Unusually low levels of oxygen and high levels of carbon dioxide would strongly suggest ischaemic priapism (low blood flow).

If non-ischaemic priapism is suspected due to an injury to your genitals or the surrounding area, you may be referred for a scan, such as an ultrasound scan. This will help identify problems with the blood vessels in your penis.


Page last reviewed: 10/02/2015

Next review due: 10/02/2017