Many boys wet the bed until puberty. My brothers both wet the bed until they hit puberty as well as my husband and one or two of my uncles.
Some things that my mother did was to move dinner up...and they were only allowed a small glass of beverage after they ate. Then they went potty before bed and then mom set her alarm to get them both up twice a night. It took a little while before she figured out their pattern, but that's what she did for years and that's the only way she was able to save herself the trouble of washing sheets everyday.
On a sadder and more serious note...(and mind you this was over 20 years ago) We were military and a doctor suggested a medicine for my brothers that worked wonders. It worked so well that my aunt went to her doctor and asked about it for her son. They put him on it and it did wonders. Then one day he wet his pants in first grade...he was six. His dad gave him a hard time when he got home and called him a baby and so on. That night when his mom was getting the baby ready for bed...he climbed the counter and got in the cabinet. He took the whole bottle of medicine. All anyone can figure is he reasoned to himself that if one pill kept him from wetting the bed...the whole bottle would keep him from wetting in class again. His 3 year old brother watched and he told him not to tell. Later that night he screamed he was falling and when his dad went to see what was wrong little Clifford went into convulsions and stopped breathing. His dad did CPR for 30 minutes until the paramedics arrived, but he never recovered. After about two weeks, several operations to relieve pressure on his brain and several ressusitations...his parents let him go. He turned seven in the hospital. I'll never forget little Clifford. The day my family moved to AZ from SC little Clifford cried and cried and said he would never see his sissy again (me). We tried to reassure him that I would move back, but he couldn't be consoled and his mom said he cried for hours after we drove away. He was right I never saw him again. His dad started drinking heavily after that..he blamed himself until he died at 57 of a massive heart attack. A lady wrote a book about experimental drugs doctors were giving patience without fully disclosing that they weren't fully approved. The military could do that back then without reprucussions. Turned out the drug had built up in his system and by the time he took the overdose he already had so much in his system that even though they pumped his stomach it was too late.
Now I know that laws have changed and so has medicine, but as you seem to have noted in your posting you seem weary of using a drug ...and I agree. Always be weary of using a drug to treat something so insignificant in the whole scheme of things.
Try some of the techniques my mom used and see if you can at least limit the number of times he has accidents. And if I remember milk was a bad beverage for my brothers at night. They always wet the bed with that for some reason. Not sure about that one though. Try another beverage in small amounts.
Good luck...I'm having a baby boy this time and I worry he will inherit my brothers' bedwetting problems....but I guess if that's his only health issue I will be happy.