Nasal spray to cause seizures

Desmopressin intranasal spray has been linked to seizures in at least a dozen Australian patients, seven of which were children. Desmopressin nasal spray is often used to treat bedwetting in children.

Desmopressin is a hormone taken through the nose, by mouth, or given by injection to prevent or control the frequent urination, increased thirst, and loss of water associated with diabetes insipidus (water diabetes). Desmopressin is used also to control bed-wetting and frequent urination and increased thirst associated with certain types of brain injuries or brain surgery. Desmopressin works by acting on the kidneys to reduce the flow of urine.

Last year, the U.S. Food & Drug Administration (FDA) warned that certain patients taking desmopressin are at risk for developing severe hyponatremia that can result in seizures and death. Hyponatremia is an electrolyte disturbance (disturbance of the salts in the blood) in which the sodium concentration in the plasma is too low.

The warning came after the FDA reviewed 61 postmarketing cases of hyponatremic-related seizures associated with the use of desmopressin, including 2 fatalities. Thirty-six cases were associated with intranasal formulations of desmopressin, of which 25 cases occurred in pediatric patients. At the time of last year’s FDA alert, the agency said that the use if intranasal Desmopressin was no longer indicated for bedwetting.

Now, Australia’s Therapeutic Goods Administration (TGA) says it has received 68 reports of adverse reactions linked to the drug. There were 17 reports of convulsions and a further 10 of hyponatremia. The side-effects were mostly seen with the nasal spray formula.

“Of 12 reports of convulsions or hyponatremia following the use of desmopressin nasal spray, seven involved children under 13 years of age,” the TGA said in its latest adverse drug reactions bulletin. The product will not be removed from sale, but the TGA warned doctors to prescribe the product only when a bed-wetting alarm device has failed to work.