OTC Feldine P gel helps as a spot treatment. It is only a painkiller. Voltarol gel is ibuprofen so anti-inflammatory painkiller. Co-codamol is also OTC in three strengths. Boots sell codeine with ibuprofen. Anything with codeine can be addictive though. These things might not work but if he can go to the doctor and say he is taking OTC stuff daily and needs something stronger to be effective pain relief they might take him more seriously. There are lots of prescription painkillers to try he does not have to tolerate the pain for the rest of his life.