Here's why different painkillers are only effective for certain types of pain

Whether it’s your head, tooth, or back, when you’re in pain, it’s hard to think about anything else. If it’s not too strong, some can ride it out. But in many cases, the pain just gets worse and won’t go away until you take something. Medicines that kill pain are called analgesics and they vary in how they work. No single painkiller can relieve all types of pain. Those that work for mild pain usually have little effect on severe pain unless combined with a stronger painkiller.

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