A study of the effectiveness of the drug terbutaline on controlling nighttime hypoglycemia in people with type 1 diabetes indicates that it may be a safe and useful treatment with no ill effects.
Researchers at the Washington University School of Medicine in St. Louis studied 15 type 1 patients (average A1c: 7.1%) to see if terbutaline could prevent hypoglycemic episodes during sleep without causing hyperglycemia the following morning.
(Terbutaline, which goes under the trade names Brethine, Bricanyl, and Brethaire, is typically used as a fast-acting bronchodilator in asthma patients. Doctors also use it to delay premature labor.)
Some patients were randomly assigned a dose of 2.5 mg of terbutaline each night before going to sleep. A second group received a 5 mg dose. A third group received a placebo. The patients received their respective doses at 10 p.m. on three separate nights.
The mean lowest plasma glucose concentrations at night among the groups were:
- 2.5 mg: 100 mg/dl
- 5 mg: 122 mg/dl
- Placebo: 87 mg/dl
Morning plasma glucose levels were:
- 2.5 mg: 127 mg/dl
- 5 mg: 183 mg/dl
- Placebo: 113 mg/dl
Although the mean figures for the 2.5 mg terbutaline group seem to be closer to the ideal, seven patients in the group reached a nadir nocturnal concentration of 70 mg/dl; six reached 60 mg/dl; and two reached 50 mg/dl in the course of the study. While three patients in the 5 mg group reached a nadir of 70 mg/dl, none in the group reached a lower level.
The researchers had previously reported on the effectiveness of a 5 mg dose of terbutaline, but were concerned that its morning plasma glucose levels were high. While the study tentatively established the effectiveness of the 2.5 mg dose, researchers have called for a much longer, more extensive trial of the drug among type 1s.