From the Guidelines
The primary risk associated with desmopressin (DDAVP) therapy is the development of hyponatremia, particularly if combined with excessive fluid intake, as highlighted in a study published in The Journal of Urology 1. This risk is significant because desmopressin increases water reabsorption in the kidneys, potentially diluting sodium levels in the blood if fluid intake is not properly managed. To mitigate this risk, patients on desmopressin should be advised to limit their fluid intake, with a general recommendation being an evening intake of 200 ml (6 ounces) or less and then no drinking until morning, as suggested by the study 1. Key considerations for managing the risk of hyponatremia with desmopressin therapy include:
- Restricting fluid intake appropriately to avoid water intoxication
- Monitoring serum sodium levels regularly, especially when initiating therapy or adjusting the dosage
- Educating patients on the early signs of hyponatremia, such as headache, nausea, confusion, and lethargy, and the importance of seeking immediate medical attention if these symptoms occur
- Being aware that certain populations, like the elderly, may be at a higher risk for complications from hyponatremia, which can range from mild to severe manifestations including seizures, coma, and death in extreme cases. Given the potential for serious complications, it is crucial to prioritize careful management and monitoring of patients on desmopressin therapy to minimize the risk of hyponatremia, as emphasized by the evidence from the study 1.
From the FDA Drug Label
WARNINGS Very rare cases of hyponatremia have been reported from world-wide postmarketing experience in patients treated with desmopressin acetate. Desmopressin acetate is a potent antidiuretic which, when administered, may lead to water intoxication and/or hyponatremia.
PRECAUTIONS General ... Desmopressin acetate 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.
The risk of hyponatremia with desmopressin (DDAVP) therapy is present, particularly in patients with conditions associated with fluid and electrolyte imbalance. Hyponatremia can be fatal if not properly diagnosed and treated. Patients should be observed for signs and symptoms associated with hyponatremia, such as headache, nausea/vomiting, and decreased serum sodium.
- Key factors that increase the risk of hyponatremia include:
- Conditions associated with fluid and electrolyte imbalance (e.g., cystic fibrosis, heart failure, renal disorders)
- Habitual or psychogenic polydipsia
- Concomitant administration of drugs that may increase the risk of water intoxication with hyponatremia (e.g., tricyclic antidepressants, selective serotonin re-uptake inhibitors) 2 2
From the Research
Risk of Hyponatremia with Desmopressin (DDAVP) Therapy
- The risk of hyponatremia is a known complication of DDAVP therapy, as reported in a case series study 3.
- A study published in 2004 noted that the major complication of DDAVP therapy is water intoxication and hyponatremia, which can be reduced by careful dose titration and close monitoring of serum osmolality 4.
- Severe hyponatremia due to desmopressin has been reported, highlighting the need for awareness of this potential complication, even in asymptomatic patients 5.
Management of DDAVP-Associated Hyponatremia
- Discontinuing DDAVP in patients with symptomatic DDAVP-associated hyponatremia can lead to rapid correction of serum sodium and resultant severe neurological injury 3.
- Continuing DDAVP while correcting hyponatremia with intravenous hypertonic saline may lead to better outcomes by avoiding over-correction of serum sodium 3, 6.
- Desmopressin can be used to minimize water excretion during the correction of hyponatremia, and clinicians should monitor closely to avoid free-water diuresis 6.
Epidemiology of Hyponatremia with DDAVP Therapy
- A population-based cohort study found that the rate of hyponatremia was 13-fold higher in adults prescribed desmopressin compared to those prescribed oxybutynin 7.
- The study reported a rate of hyponatremia of 146 per 1,000 person-years for adults prescribed desmopressin, highlighting the need for clear communication of this risk to patients 7.