Question: how many times a day can you give a dog robitussin?
Answer: In general, 2 mg per 50 pounds, twice daily. For coughing: –Dextromethorphan (Robitussin DM with dextromethorphan at 10-15 mg/5ml and Guafenisin at 100mg/5ml), for cough. Roughly, 1 teaspoon per 20 pounds for dogs.