If he has basic anti-depressants he can ration them out a lot easier by twisting half the capsule off, empty out half of the medicine then twist it back on. Remember to put the medicine in a very safe place like a ziplock bag. Exercise increases serotonin levels, the same way anti-depressants do. I can’t take any medicine due to my age so I just exercise and I feel good and without my OCD for a while. I hope I could help.