Well the answer to this is difficult since they both do different things. Pain killers relieve pain and depressants help with the lack of serotonin. But the painkillers and anti- depressants are killing more people each year because they are abusing the drugs. So the answer in my mind would be pain killers because it gets rid of pain and it makes you have side effects such as hallucinations. Depressants just make you drowsy at most.