Possible Clues:

• The relief of pain by drugs
• Arranging sale again proves no pain
• Angela is a little upset with pain-killer
• One country that's right to be ejected for society's painlessness
• An African nation had succeeded in eliminating resistance, which is a relief
• Relief of pain in a leg as a result of treatment?
• Broken a leg? Asian is given pain relief
• Insensibility to pain? That's a new angle in 6
• Freedom from aches and pains - unusual in age alas!
• A gas alien concocted for the relief of pain