Phimosis is the medical term for a tight foreskin that will not pull back over the glans (head of the penis).
This is normal in babies and toddlers, but in older children it may be due to a skin condition that has caused scarring.
When phimosis is normal
Almost all uncircumcised babies have a foreskin that will not retract (pull back) because it is still attached to the glans. At this age phimosis is perfectly normal, and the foreskin should be left alone.
Generally, the foreskin stays like this until the child is about two years old. By this time, the foreskin separates naturally from the glans.
In some children, it may take longer for the foreskin to become unstuck. This does not necessarily mean there is a problem.
You should never try to force your child's foreskin back when it is not ready, as this can damage the foreskin and make the problem worse.
When phimosis is a problem
Phimosis is not usually a problem unless it is causing symptoms. If symptoms are present the tight foreskin is probably the result of irritation from urine or an infection and you will need to see your GP. Treating the irritation or infection will usually clear the problem.
If there is swelling, soreness and redness around the glans and foreskin, sometimes with a thick discharge under the foreskin, the cause is probably balanitis. Balanitis is not serious and can usually be cured with bathing. A steroid cream may need to be applied and antibiotics are sometimes necessary.
The most common cause of balanitis in young boys is not getting rid of excess urine from the end of the penis after urinating.
Balanitis can sometimes be confused with a urinary tract infection, which causes pain when urinating, a feeling of needing to urinate urgently and blood in the urine. This will need treatment with antibiotics.
If your son has a tight foreskin caused by regular episodes of balanitis, surgery may be necessary. This may either be circumcision (surgical removal of the foreskin) or surgery to release the adhesions (patches where the foreskin has become stuck to the glans). Surgery to release adhesions preserves the foreskin but may not prevent the problem recurring.