Hip Joint supplement overdose?

[Axle2009]

I've had my GSD on a hip and joint supplement for some time. About 6 month ago I switch him over to a different brand. Someone I got the dosage mixed up and i've been giving him too much. The label calls for this...

Give 1/2 chewable per 40 lbs. of body weight, twice daily. Allow four to six weeks for best results. Continue as needed.

Ingredients: 500mg Green Lipped Mussel, 400mg Glucosamine, 400mg MSM.

Now my GSD weighs is right about 68lbs. I was giving him 2 tablets per day (one in the morning and one at night). Do you think I did any damage by doing this? Should I pull him off of it for a short time and restart on the right dosage or just keep going at one pill per day now?