Used a vial of deca. Used up half the vial last year. All the shots taken from the vial were administered, combined with test, with minimal discomfort. Vial was stored in optimal conditions for about a year, and is still well within its expiration. Recently tried to use the vial again, and upon administering, the test/deca solution burned horribly. Horribly. Anyone know why it suddenly became so harsh.