Priapism in sickle cell disease

Priapism is an unwanted erection of the penis that lasts longer than 30 minutes. It is not caused by sexual desire, arousal, or stimulation. It can often be painful and distressing.

Priapism can cause damage to your penis if it’s not treated quickly.

At worst, it can stop you from having a regular erection. 

Causes of priapism

Priapism is common in males with sickle cell disease

During a usual erection, blood flows into the penis and it becomes rigid. After ejaculation, hormones are released which allow the blood to drain.

If sickled red blood cells cause a blockage, the blood cannot drain, and the penis stays erect. 

When someone has a priapism, this is known as an episode. 

The types of priapism include:

Stuttering priapism

Recurring episodes that are short, and last from a few minutes to several hours. 

Fulminant priapism

Longer episodes that can last for 4 hours or more. 

Priapism associated with low blood flow 

This is linked to sickle cell disease and happens when the vein that usually lets blood run from the penis is blocked. This may lead to tissue damage.

Priapism associated with high blood flow

This is very rare in sickle cell disease. It happens after injury to the penis, when the cavernosal artery (vein leading to the penis) becomes damaged. 

Other causes

Other causes of priapism include:

• injury to the penis or genital area

• damage to the nervous system


• leukaemia and multiple myeloma

• drinking alcohol or taking recreational drugs

How to prevent it

To prevent triggering a priapism episode, you can:

• avoid alcohol, cannabis, tobacco and Viagra ®, as these can trigger priapism, or make it worse

• keep well hydrated (drink enough fluids) 

Sometimes priapism might still happen, despite these precautions. If you have had it before, your haematologist might ask you to take a medicine, such as etilefrine, on a regular basis. This can prevent it from recurring.

If you get a priapism

If you have a priapism, you should immediately:

• drink lots of fluids

• take regular painkillers, such as paracetamol if you need to

• try to pee (pass urine)

Some people also find that jogging or other types of exercise help.

These should help to stop the episode within 1 hour. It is important that you report any episodes of priapism to the haematology team.

Go to the emergency department (A&E) immediately if:

  • a priapism has not resolved within 2 hours

There is a risk of permanent damage if priapism lasts longer than 4 hours.

If you can, go to St Thomas’ Hospital A&E directly to avoid delay in receiving treatment.

Emergency treatment

If you have gone to A&E for emergency treatment, you will be seen by a haematologist and a urologist to decide which treatment you need. 

There are different treatments to help reduce the erection. These include:

  • Medicines, such as etilefrine, which is usually given by mouth or may be given by injection into the penis. A different medicine which stops erections by lowering testosterone might also be used. 
  • Drainage of some blood from the penis.
  • Numbing the penis with local anaesthetic and then using a small needle to check how much acid and oxygen there is in the blood. This procedure is very important to save future penile function.
  • Sometimes surgery might be needed. Your haematology or urology team can provide more information on this.

It is important to understand that your urologist is trying to prevent more severe and lasting damage, which can result in erectile dysfunction, and to treat this severe emergency. 


Do not try to treat erectile dysfunction yourself, as some treatments, including those that you buy online, may be harmful. 

Problems caused by priapism

Some patients who have had priapism have difficulties having regular erections when they want one. Erectile dysfunction is more likely to happen if priapism episodes are not treated immediately. Erectile dysfunction can cause severe psychological distress and affect relationships.

If you feel that you have developed erectile dysfunction, it is important that you are checked by a urologist to talk about your treatment options. Your GP or haematology team can refer you to a urologist. Urologists often do clinics jointly with haematologists to manage both your sickle cell disease and the effect on your penile function. 

Resource number: 3501/VER5
Date published: January 2024
Review date: January 2027

Contact us

If you have any questions about priapism, or your treatment at St Thomas' Hospital, please contact the consultant haematologist’s secretary. 

Phone: 020 7188 2741, or phone: 075 4815 2680

Or, you can contact the clinical nurse specialist.

Phone: 020 7188 1424, or email: [email protected]   

Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

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