What If We Could Swallow Medicines Instead of Needing Painful Injections?

People usually take medicines by swallowing a tablet or pill, but many important medicines cannot be taken by mouth. Vaccines, for example, must be injected using a needle and syringe. You might know people who have diabetes, a condition in which the body does not make enough of the hormone insulin. Insulin allows your cells to use the sugar in your blood for energy. People with diabetes must take insulin to be able to lower their blood sugar levels. Unfortunately, people cannot take insulin by mouth because the acid in the stomach will attack it like food. Insulin is also large and cannot cross the wall of the intestine to get into the blood, which is where it needs to go. Instead, people must take insulin by injecting it into the blood. But what if medicines, like insulin, could be designed so they could be swallowed instead of being injected?