The description you have given suggests of following:
1. Cervical Spondylitis- it happens due to long hours of sitting work like more of writing/reading paper work or more usage of laptops/computers.
2. Anxiety/panicky/stressful situations leading to frequent headaches
and mood swings.
3. Migraine- presents as one sided headaches accompanied with nausea vomiting
The medication you have mentioned is suggestive of pain and stress. Ask him to take a break from work and have a short holiday with lots of rest and relaxing schedules. Migraine is less likely to be there, out of the other two causes it could be any. You can do the following:
1. Brisk walk twice a day at least for a 20 minutes session, during walk no talkings/cell phones only walk.
2. Add a few almonds and walnuts in his diet.
3. Ask him to sleep atleast for 6-7 hours a day.
4. Donot load him with bulk of issues and problems make it a few at a time.
5. Try to share his work load and make his environment easy.
6. Help him in reducing a few pounds too.
Wish you a speedy recovery to health, feel free to come up with any queries you have.