Pramlintide (Symlin) is a synthetic amylin analogue. First described in 1987, amylin is a neuroendocrine hormone produced by beta cells, which also produce insulin. This hormone is absent in type 1 diabetes and decreased in type 2 diabetes.
Both hormones are released in response to a rise in blood glucose levels. When used with insulin, three major actions occur: appetite suppression, suppression of abnormal post-meal glucagon release that stimulates the liver to release glucose, and delayed digestion of food through the digestive system, permitting slower absorption of glucose from the gut to circulation. Because these actions lower glucose levels, it is necessary to reduce the pre-meal fast-acting insulin dose by 30 to 50 percent when starting to use this additional therapy.
At this time, pramlintide is injected subcutaneously, but it is not approved for delivery via an insulin pump. The only recommended injection sites are the abdomen and upper thigh. Insulin and pramlintide should never be mixed in the same syringe.
Doses start at 15 micrograms (2.5 units by 30-unit insulin syringe) and are gradually increased to a maximum of 60 micrograms (10 units) for type 1s, and 60 to 120 micrograms (10-20 units) for insulin-using type 2s.
Injection is before meals and snacks containing at least 250 calories or at least 30 grams of carbohydrate. Peak action is reached in 20 minutes and diminished over three hours. If you are not eating, it is not injected.
Benefits for pump users
Less insulin use, reduced post-meal glucose spikes, decreased appetite, lower A1C levels and weight loss have been reported by users of pramlintide.
Bolus delivery adjustments needed
Recommended pre-meal bolus reduction starts at 50 percent. Some individuals may need less of a reduction. This can be determined with good BG recordkeeping and communication with the medical team.
Hypoglycemia can occur within three hours of injection and if bolus decreases are not made. A burning sensation at the injection site. Three-hour post-meal hyperglycemia. Some pump users have experimented with the dual wave/combination bolus timing as a method to decrease risk of this problem. Nausea at initial use that should decrease over time or with a reduction in dose.
For more detailed information about who can and cannot use this therapy, contact your diabetes care provider, or go to www.symlin.com or call (800) 349-8919. The Web site information was updated in January 2006.
For more about Symlin, see the article “FDA Approves Symlin, a New Treatment Option for Type 1s and Insulin-Using Type 2s,” by Daniel Trecroci (Diabetes Health, June 2005).