Subcutaneous Delivery System Research Articles

Sustained-release subdermal estradiol implants: A new alternative in estrogen replacement therapy

This trial was a therapeutic and pharmacokinetic dose-finding study with subdermal implants that showed a constant in vitro daily release rate of estradiol. The aim was to find the daily release rate of estradiol that produces serum estradiol concentrations comparable with those obtained with transdermal estradiol at 0.05 mg/day. The study was an open crossover comparison of transdermal and subcutaneous delivery systems. Thirty-six postmenopausal (serum follicle-stimulating hormone concentration > 30 IU/L before commencing the study) were treated with transdermal estradiol for 4 weeks. Immediately after this transdermal estradiol delivery was replaced by either one or three estradiol implants. The serum concentrations of estrone, estradiol, follicle-stimulating hormone, and sex hormone-binding globulin were followed up for 8 weeks on implant therapy and compared with those during transdermal estrogen administration. To oppose the estrogen effect on the endometrium, each patient received an intrauterine device releasing a progestin, levonorgestrel. The serum estradiol concentrations achieved with three implants were comparable with those during transdermal administration of estradiol at 0.05 mg/day. Suppression of follicle-stimulating hormone was also better maintained with three implants compared with one. This study shows that constant release profiles can be achieved with nonbiodegradable estradiol implants. The results suggest that a single application should give sufficient estrogen substitution for more than a year.

Insulin Therapy in Insulin-Dependent (Type I) Diabetes Mellitus

Intensive insulin therapy is suitable for individuals who want optimal glucose control and the least fluctuation in glucose levels. It permits a greater flexibility in life style and the opportunity to vary, within certain limits, meal and exercise schedules and meal content. This therapeutic approach is modeled on physiologic insulin secretion, but shortcomings in the subcutaneous route of delivery hamper the ability to control precisely the glucose levels. The therapy is most successful when the user is motivated to do the glucose monitoring and carbohydrate counting and educated to make rational decisions about how to adjust the insulin doses.

A simplified approach to the subcutaneous placement of epidural catheters for long-term administration of morphine.

Abstract The use of intraspinal narcotics to relieve pain of malignant origin represents a great advance in cancer pain management. For patients with a relatively short life expectancy, the delivery of intraspinal narcotics may be carried out using an as needed single-shot approach or via a simple percutaneous catheter. For patients with a longer life expectancy, implantation of subcutaneous delivery systems has been advocated to avoid complications including infection and catheter breakage. A simplified approach to placement of subcutaneous epidural catheters utilizing the Groshong silastic catheter and tunneling device is described.

Lactogenesis and control of prolactin in cows

This paper reviews the physiological, endocrinological and pharmaceutical literature pertaining to the design, development and optimisation of subcutaneous and intravaginal progestogen-containing drug delivery systems used in the control of synchrony and ovulation in cattle.