Drug Name Reglan

Foscarnet represents a diphosphate analogue. As shown in (A), incorporation of nucleotide into a DNA strand entails cleavage of a diphosphate residue. Foscarnet (B) inhibits DNA polymerase by interacting with its binding site for the diphosphate group. Indications: systemic therapy of severe cytomegaly infection in AIDS patients; local therapy of herpes simplex infections.
Direct Parasympathomimetics. The choline ester, carbachol, activates M-cholinoceptors, but is not hydrolyzed by AChE. Carbachol can thus be effectively employed for local application to the eye (glaucoma) and systemic administration (bowel atonia, bladder atonia).

 

Accordingly, for protonated substances, the extent of reabsorption is dependent upon urinary pH or the degree of dissociation. The degree of dissociation varies as a function of the urinary pH and the pKa, which represents the pH value at which half of the substance exists in protonated (or unprotonated) form.
In the case of released ACh, rapid breakdown by ACh esterase allows repolarization of the endplate and hence a return of Na channel excitability in the adjacent sarcolemma. With succinylcholine, however, there is a persistent depolarization of the endplate and adjoining membrane regions. Because the Na channels remain inactivated, an AP cannot be triggered in the adjacent membrane.