The medicine you take for one physical disorder may literally rot your teeth. This is one of many reasons we need to know your medical history and current treatment.
Chewable vitamin C supplements are a good idea for a lot of people, but check your brand for sugar content. For children especially, a liquid form does less damage to tooth enamel, and natural sources of the vitamin—oranges, green vegetables—are even better.
Calcium channel blockers (Procardia, Cardizem, Adalat) cause swelling of the gums in at least 20% of patients with high blood pressure or heart disease. This can be very dangerous, as bacteria invade gums and may reach the heart itself.
Over-the-counter preparations of all sorts—lozenges, cough drops, antacids—are sugar-laden. Tums has calcium, yes, and enough sugar for a family of four.