Existing higher-dose formulations of desmopressin are indicated for use only in patients up to 65 years, because of the increased risk of hyponatraemia in the elderly. However, with the recommended monitoring of serum sodium, Noqdirna can be used in patients over 65 years.
The once-daily sublingual tablets are available in gender-specific doses of 50 microgram for men and 25 microgram for women, both taken one hour before bedtime. To reduce the risk of fluid overload, fluid intake should be limited to a minimum from one hour before and until eight hours after administration.
Difficult to treat
"Nocturia is a very common symptom encountered in primary care and can be very difficult to treat effectively," said Jonathan Rees, a GP in North Somerset and Founder of the Primary Care Urology Society.
"We know that nocturia can have a significant impact on quality of life, and also increased risk of falls and fractures. Nocturnal polyuria often does not respond to lifestyle changes or medication currently available, so the addition of Noqdirna to our armoury is highly welcome, particularly as we can now use this in patients over 65 unlike existing desmopressin formulations."
Fewer night-time voids
The effect of low-dose desmopressin on nocturia was evaluated in separate randomised, double-blind trials in (n=385) and (n=261).
Over 3 months of treatment, desmopressin reduced the average number of night-time urinations from baseline compared with placebo by 0.22 in women (p=0.028) and 0.37 in men (p=0.0003). The number of patients with at least a 33% decrease in the mean number of nocturnal voids nearly doubled with desmopressin treatment, with odds ratios of 1.98 in men (p=0.0009) and 1.85 in women (p=0.006) compared with placebo.
Nocturnal urine volume, a secondary endpoint, decreased by 209ml in men treated with desmopressin and 235ml in women treated with desmopressin, compared with 131ml and 151ml, respectively, in men and women receiving placebo (p=0.009 and p=0.003, respectively).
Desmopressin was well tolerated by both men and women, according to the investigators. The most commonly reported adverse reactions were dry mouth (13%), headache (3%), hyponatraemia (3%), and dizziness (2%).
Desmopressin is analogue of endogenous vasopressin. It binds to specific receptors in the kidneys, concentrating urine and leading to reduced night-time urine production.