system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following is not a teiary amine derivative?
assistant
The correct answer is  Ans. b. Glycopyrrolate Glycopyrrolate is a synthetic quaternary anticholinergic drug, which doesn't cross the blood brain barrier and completely lacks central effects.