Authors and Disclosures
Laura S. Lehman, PharmD| Pharmacist, Carroll Hospital Center, Westminster, Maryland
Disclosure: Laura S. Lehman, PharmD, has disclosed no relevant financial relationships. |
From Medscape Pharmacists > Ask theExperts
Why Use Isosorbide Dinitrate vs Isosorbide Mononitrate?
Laura S. Lehman, PharmD
What is the difference or advantage of using isosorbide dinitrate over isosorbidemononitrate?
| Response from Laura S. Lehman, PharmD
Pharmacist, Carroll Hospital Center, Westminster, Maryland |
Isosorbide is a nitrate vasodilator available in various oral forms, whichinclude inexpensive generic versions. Isosorbide dinitrate (ISDN) is an intermediate-acting nitrate approved for prevention of angina pectoris. It is also used in conjunction with hydralazine intreating congestive heart failure, particularly in African Americans who have inadequate response to optimal medical therapy. The US Food and Drug Administration (FDA)-approved formulation for heartfailure is the fixed combination of ISDN/hydralazine tablet (BiDil®). Isosorbide dinitrate is also available in immediate-release (eg, Isordil®) and extended-release (eg, Dilatrate-SR®) forms. Thebioavailability of ISDN varies widely, and it undergoes significant first-pass metabolism. The half-life of ISDN is about 1 hour. When ISDN is administered in 3 to 4 doses daily, nitrate tolerance candevelop, rendering the agent less efficacious.
Isosorbide mononitrate (ISMN) is the active metabolite of ISDN and is primarily used in the management of chronic stable angina. It is not FDA-approved fortreating heart failure. It has high bioavailability and a longer half-life (4-6 hours) than ISDN. The immediate-release form (eg, ISMO® and Monoket®) is typically given in 2 doses daily 7 hours...