Hi i am prescribed 240 mgs of Dihydrocodeine per day for a pretty serious spinal injury sustained 3 years ago, refusing now to take anything with paracetamol in i was on Codeine Phosphate, i found these not to be working so now i get 168 of the Dihydrocodeine instead, my question is will Promethazine Hydrochloride increase the effectiveness of the drug so i can therefore use less than 240mgs per day?