Oral Peptides

Many peptides need to be administered parenterally, which is to say they need to bypass the gastrointestinal system (stomach, intestines, etc.). The most common means of parenteral administration is via injection, but there are other methods including nasal inhalation, topical creams, suppositories, eye drops, and more. But, the most convenient way to take something is by mouth – it is quick, simple, and painless. So, why is it that so many peptides need to be taken by injection? The answer come