I'm a little confused by this however I think that I understand it enough to give some input.
When poisoned, a Pokemon with Poison Heal will recover 1/8th of its health at the end of each turn. You aren't supposed to lose the poison status after the turn ends, it's stays with you until the end of the battle or until removed via other causes. This is why Pokemon like Breloom and Gliscor can be extremely effective whilst poisoned.