Note: This is the second part of a two-part series. The first partwas published in our January 2005 issue
Meglitinides and Phenylalanine Derivatives
The meglitinide class of drugs includesPrandin (repaglinide). The phenylalanineclass includes Starlix (nateglinide).
These two drugs came onto the U.S. marketin the mid 1990s and have found a nichein the treatment of certain people withtype 2 diabetes.
As cousins to the sulfonylureas, thesemedications also require at least somepancreatic beta cell function to work. Theystimulate insulin faster and for a shorterperiod of time than the sulfonylureas.Therefore, for maximum effectiveness and tominimize possible hypoglycemia, they mustbe taken with the first bite of every meal thatcontains carbohydrate.
The main benefits of these drugs is that theyhave less incidence of hypoglycemia andprovide greater flexibility in terms of mealsand exercise than the sulfonylureas. Thedrawbacks are that patients often forget totake them with the afternoon meal, and theyare much more expensive and less potentthan the sulfonylureas.
These drugs do not lower blood glucose;instead, they prevent it from rising overnightand before meals. Metformin, also marketedas Glucophage or Glucophage XR, is the onlybiguanide currently available in the UnitedStates. This drug reduces the amount ofstarch breakdown by the liver in the fastingstate and for several hours after eating.
Metformin offers several unique and helpfulfeatures for patients:
- It does not cause weight gain (weight neutral)
- It may actually help with weight loss
- It lowers cardiovascular risk
- It restores ovulation in some women with polycystic ovary syndrome (an insulin-resistant condition)
The main side effects of metformin arenausea and diarrhea, which can be limitedby taking it with or after meals and bystarting with the lowest possible dose.
Patients with kidney or liver disease or whohave a history of alcohol abuse or congestiveheart failure should not take this medication.