 [ Symptoms ] i have a harden penis that dose not reduce [ Disease ] i suggest you seek immediate medical attention it sounds like you are describing priapism which is a prolonged erection not caused by sexual stimulation in priapism blood gets trapped within the penis causing it to remain erect if this is not treated quickly it can cause permanent damage you may have heard this on commercials but if you ever experience an erection lasting longer than 4 hours seek medical attention this condition does not result only from the use of drugs for erectile dysfunction it can occur in any healthy man take care