From the Research
The maximum daily dose of urea is typically 40 grams per day when used as a medication. For topical applications in dermatology, concentrations of 10-40% are commonly used, with no strict maximum daily amount specified as absorption through skin is limited. When used orally for conditions like syndrome of inappropriate antidiuretic hormone secretion (SIADH) or increased intracranial pressure, doses usually start at 15-30 grams per day divided into multiple doses and can be increased as needed up to the 40-gram maximum, as seen in a study published in 2022 1. Urea works as an osmotic diuretic by increasing the excretion of water and solutes in the urine, and topically it acts as a keratolytic agent that softens and hydrates the skin by breaking down proteins.
Key Considerations
- Patients should be monitored for potential side effects including nausea, vomiting, headache, and electrolyte imbalances, with a study from 2019 2 showing that urea is safe and effective in fluid restriction-refractory hyponatraemia.
- Adequate hydration should be maintained during treatment, and urea should be used cautiously in patients with renal or hepatic impairment.
- A study from 2020 3 suggests that oral urea appears to be an effective, safe, and well-tolerated therapeutic strategy in the management of chronic hyponatremia.
Dosage and Administration
- The dose of urea can be adjusted based on the patient's response and tolerance, with a median dose of 30 g/day used in a study published in 2022 1.
- Urea can be administered orally, typically in divided doses, to minimize gastrointestinal side effects.
Potential Side Effects and Interactions
- Common side effects of urea include nausea, vomiting, and headache, as reported in a study from 2018 4.
- Urea can interact with other medications, such as diuretics, and should be used with caution in patients with renal or hepatic impairment.