Which route of administration gives 100% bioavailability? a) Oral b) Intramuscular c) Intravenous d) Subcutaneous Approaches for enhancing oral bioavailability of peptides and proteins ScienceDirect Your body already produces thousands of peptides biological signalling molecules that instruct cells to repair tissue, produce hormones, regulate immunity, and protect neurons. The question longevity medicine is now asking is: Most patients on peptide therapy are not noncompliant. They follow the protocol. They take the prescribed dose. They stay consistent. And yetprogress slows. Then stalls. Month three. Month four. Month six. The