Jelqing is a purported method of enlarging the penis by exercising the parts of it that are made of muscular tissue. While it is not clear if jelqing provides any positive benefit, it can cause injury.
Jelqing is done by quickly massaging the penis and trying to force more blood into the head of the penis in the hopes of strengthening the smooth muscles that make up part of it.
Rashes can result from abrasions suffered during jelqing. These injuries can be prevented by the use of lubrication when jelqing or treated with mild skin creams.
Rough handling of the penis can result in damage to small blood vessels just under the skin, causing bruising. There is no treatment other than to let them heal.
Jelqing can also strain the ligaments at the base of the penis. While this condition is not serious, it can be painful and there is no treatment other than rest.
Burst Blood Vessels
Jelqing can cause blood vessels in the penis to burst, possibly leading to bleeding in the urethra. This condition can become serious and should be examined by a doctor.