PRECAUTIONS
General: Intranasal DDAVP at high dosage has infrequently produced a
slight elevation of blood pressure, which disappeared with a reduction in dosage.
The drug should be used with caution in patients with coronary artery insufficiency
and/or hypertensive cardiovascular disease because of possible rise in blood
pressure.
DDAVP should be used with caution in patients with conditions associated with fluid and electrolyte imbalance, such as cystic fibrosis, heart failure and renal disorders because these patients are prone to hyponatremia.
Rare severe allergic reactions have been reported with DDAVP. Anaphylaxis has been reported rarely with intravenous and intranasal administration of DDAVP.
Central Cranial Diabetes Insipidus: Since DDAVP is used intranasally,
changes in the nasal mucosa such as scarring, edema, or other disease may cause
erratic, unreliable absorption in which case intranasal DDAVP should not be
used. For such situations, DDAVP Injection should be considered.
Information for Patients: Ensure that in children administration is under
adult supervision in order to control the dose intake. Patients should be
informed that the DDAVP Nasal Spray (desmopressin acetate nasal spray) bottle accurately delivers 50 doses
of 10 mcg each. Any solution remaining after 50 doses should be discarded since
the amount delivered thereafter may be substantially less than 10 mcg of drug.
No attempt should be made to transfer remaining solution to another bottle.
Patients should be instructed to read accompanying
directions on use of the spray pump carefully before use.
Fluid intake should be adjusted downward based upon discussion with the physician.
Laboratory Tests: Laboratory tests for following the patient with central
cranial diabetes insipidus or post-surgical or head trauma-related polyuria
and polydipsia include urine volume and osmolality. In some cases plasma osmolality
measurements may be required.
Carcinogenesis, Mutagenesis, Impairment of Fertility: Studies with DDAVP
have not been performed to evaluate carcinogenic potential, mutagenic potential
or effects on fertility.
Pregnancy: Category B: Fertility studies have not been done.
Teratology studies in rats and rabbits at doses from 0.05 to 10 mcg/kg/day (approximately
0.1 times the maximum systemic human exposure in rats and up to 38 times the
maximum systemic human exposure in rabbits based on surface area, mg/m2)
revealed no harm to the fetus due to DDAVP (desmopressin acetate). There are,
however, no adequate and well controlled studies in pregnant women. Because
animal reproduction studies are not always predictive of human response, this
drug should be used during pregnancy only if clearly needed.
Several publications of desmopressin acetate's use in the management of diabetes
insipidus during pregnancy are available; these include a few anecdotal reports
of congenital anomalies and low birth weight babies. However, no causal connection
between these events and desmopressin acetate has been established. A fifteen
year Swedish epidemiologic study of the use of desmopressin acetate in pregnant
women with diabetes insipidus found the rate of birth defects to be no greater
than that in the general population; however, the statistical power of this
study is low. As opposed to preparations containing natural hormones, desmopressin
acetate in antidiuretic doses has no uterotonic action and the physician will
have to weigh the therapeutic advantages against the possible risks in each
case.
Nursing Mothers: There have been no controlled studies in nursing mothers.
A single study in a post-partum woman demonstrated a marked change in plasma,
but little if any change in assayable DDAVP in breast milk following an intranasal
dose of 10 mcg. It is not known whether this drug is excreted in human milk.
Because many drugs are excreted in human milk, caution should be exercised when
DDAVP is administered to a nursing woman.
Pediatric Use: Central Cranial Diabetes Insipidus: DDAVP Nasal
Spray has been used in children with diabetes insipidus. Use in infants
and children will require careful fluid intake restriction to prevent possible
hyponatremia and water intoxication. (See WARNINGS.) The dose must be
individually adjusted to the patient with attention in the very young to the
danger of an extreme decrease in plasma osmolality with resulting convulsions.
Dose should start at 0.05 mL or less.
Since the spray cannot deliver less than 0.1 mL (10 mcg), smaller doses should be administered using the rhinal tube delivery system. Do not use the nasal spray in pediatric patients requiring less than 0.1 mL (10 mcg) per dose.
Geriatric Use: Clinical studies of DDAVP Nasal Spray (desmopressin acetate nasal spray) did not include
sufficient numbers of subjects aged 65 and over to determine whether they respond
differently from younger subjects. Other reported clinical experience has not
identified differences in responses between the elderly and younger subjects.
In general, dose selection for an elderly patient should be cautious, usually
starting at the low end of the dosing range, reflecting the greater frequency
of decreased hepatic, renal, or cardiac function, and of concomitant disease
or drug therapy.
This drug is known to be substantially excreted by the kidney, and the risk
of toxic reactions to this drug may be greater in patients with impaired renal
function. Because elderly patients are more likely to have decreased renal function,
care should be taken in dose selection, and it may be useful to monitor renal
function. DDAVP is contraindicated in patients with moderate to severe renal
impairment (defined as a creatinine clearance below 50ml/min). (See CLINICAL
PHARMACOLOGY, Human Pharmacokinetics and CONTRAINDICATIONS.)
Use of DDAVP Nasal Spray (desmopressin acetate nasal spray) in geriatric patients will require careful fluid intake
restriction to prevent possible hyponatremia and water intoxication. (See WARNINGS).
There are reports of an occasional change in response with time, usually greater than 6 months. Some patients may show a decreased responsiveness, others a shortened duration of effect. There is no evidence this effect is due to the development of binding antibodies but may be due to a local inactivation of the peptide.