Editing Calcium channel blocker (section)

==== Phenylalkylamine ====
[[Image:Verapamil skeletal.svg|thumb|class=skin-invert-image|[[Skeletal formula]] of [[verapamil]]]]

Phenylalkylamine calcium channel blockers are relatively selective for myocardium, reduce myocardial oxygen demand and reverse coronary vasospasm, and are often used to treat angina. They have minimal vasodilatory effects compared with dihydropyridines and therefore cause less reflex tachycardia, making it appealing for treatment of angina, where tachycardia can be the most significant contributor to the heart's need for oxygen. Therefore, as vasodilation is minimal with the phenylalkylamines, the major mechanism of action is causing negative inotropy. Phenylalkylamines are thought to access calcium channels from the intracellular side, although the evidence is somewhat mixed.<ref>{{Cite journal |last=Hockerman, G.H. |last2=Peterson, B.Z. |last3=Johnson, B.D. |last4=Catterall, W.A. |year=1997 |title=Molecular Determinants of Drug Binding and Action on L-Type Calcium Channels |journal=Annual Review of Pharmacology and Toxicology |volume=37 |pages=361–96 |doi=10.1146/annurev.pharmtox.37.1.361 |pmid=9131258 |s2cid=16275155}}</ref>
* [[Fendiline]]
* [[Gallopamil]]
* [[Verapamil]] (Calan, Isoptin)