Clinical appreciation of LHRH analogue formulations

Luteinising hormone-releasing hormone (LHRH) analogues administered by a continuous release system produce a more complete and constant inhibition of the pituitary-ovarian axis than do multiple, daily intranasal insufflations or a once daily subcutaneous injection. In the present study, results were too limited to make a valid comparison between the clinical efficacy of various formulations in the treatment of endometriosis. A slow-release formulation is more effective in inducing amenorrhoea, but also produces more frequent and more severe clinical symptoms of oestrogen deprivation. There is no significant change in serum cholesterol levels during 6 months of treatment with any of the formulations used. During LHRH analogue treatment, the increase in urinary excretion of calcium is related to the rate and degree of serum oestradiol inhibition but the loss in bone mineral content is small and reversible after cessation of treatment. Both short-term and long-term treatment with LHRH analogues is feasible.