Which of the following provides the best explanation for neostigmine being preferred over physostigmine for treating Myasthenia gravis: (A) It is better absorbed orally, (B) It has longer duration of action, (C) It is the additional direct on agonistic action on nicotinic receptor in the muscle end plate, (D) It Penetrates blood brain barrier
Answer is C. Ref-KDT 6/e p103 Neostigmine is a quaternary ammonium derivative and is lipid insoluble. Its absorption from GIT penetration in the brain and cornea is much less than physostigmine . It produces additional action on NM receptor