<s>[INST] Hi, my grandfather is on regular Tylenol#2 every midnight. He also has a PRN Tylenol#2 to be given every 4 hrs. Sometimes, after an hour of taking his regular Tylenol#2 he complains of leg pain again. Is it safe to give him his PRN that soon even if he just had one? [/INST] Hi, Regular Tylenol#2 contains acetaminophen (325 mg or 500 mg) and is commonly used to relieve pain and fever. Whereas PNR Tylenol#2 is a combination of acetaminophen-300 mg and an opioid pain reliever codeine-15 mg which is used to relieve mild to moderate pain. Yes, PNR Tylenol#2 may be given safely as needed basis to relieve the pain but remember the total dose of acetaminophen should not exceed 3.25 g per day. Hope I have answered your question. Let me know if I can assist you further.  </s>