You could try some of the over the counter worm medicines. Most of them are formulated to kill many common worms. If you have the dog on a heart worm medicine such as Heartgard+, it should also take care of most other worms. If you didn't have him on a heart worm medicine over the summer, there is a good chance he has heartworms. If so, you must take him to a vet. He may seem fine, but with untreated heart worms, one day he will just fall over dead.
By the way, there is a dog forum here, see
https://www.askmehelpdesk.com/dogs/