The incidence of accidental dural puncture during epidural block is 2.9%; headache follows in as many as 76.5% of these patients. Treatment by injection of autologous blood into the epidural space has gained wide acceptance since its introduction in 1960, though it is contraindicated by blood dyscrasias, anticoagulant therapy, bleeding, and localized infection. The procedure is done by slowly injecting 15 to 20 ml of blood into the same interspace, no sooner than 24 hours after the original puncture. Serious complications are rare.