Minirin

Minirin is a synthetic analogue of the natural pituitary hormone 8-arginine vasopressin (ADH), containing desmopressin acetate as its active ingredient[3][5]. It functions as an antidiuretic hormone affecting renal water conservation[5]. ## Therapeutic Uses Minirin is primarily used for several conditions including: 1. **Central Cranial Diabetes Insipidus**: Minirin serves as an antidiuretic replacement therapy in the management of this condition, which causes the body to lose too much fluid and become dehydrated[1][2][5]. 2. **Primary Nocturnal Enuresis (Bedwetting)**: It's indicated for patients over 6 years of age with normal ability to concentrate urine[1][5][9]. It has shown effectiveness in some cases that are refractory to conventional therapies[5]. 3. **Nocturia in Adults**: Used for symptomatic treatment of nocturia associated with nocturnal polyuria (nocturnal urine production exceeding bladder capacity)[9]. ## Mechanism of Action The antidiuretic effects of desmopressin are mediated by stimulation of vasopressin 2 (V2) receptors, thereby increasing water re-absorption in the kidney and reducing urine production[3]. The structural change from arginine vasopressin to desmopressin acetate resulted in: - Decreased vasopressor action - Decreased actions on visceral smooth muscle - Enhanced antidiuretic activity This means clinically effective antidiuretic doses are usually below threshold levels for effects on vascular or visceral smooth muscle[3]. ## Pharmacokinetics When administered intranasally, Minirin has an antidiuretic effect about one-tenth that of an equivalent dose administered by injection[5]. It is absorbed rapidly from the nasal mucosa and exhibits a biphasic elimination profile with half-lives of 7.8 and 75.5 minutes for the initial and terminal phases, respectively[5]. ## Formulations Minirin is available in multiple formulations: - Tablets (0.1 mg and 0.2 mg)[6][9][10] - Nasal spray[3][5] ## Important Contraindications Minirin should not be used in patients who: - Are allergic to desmopressin acetate or any ingredients in Minirin - Have kidney problems - Have or have had low levels of sodium in the blood (hyponatremia)[3] - Have nasal problems that may prevent them from using a nasal spray (specific to nasal formulation)[3] Minirin is not effective in the treatment of nephrogenic diabetes insipidus[3].

Brand names

Minirin

Other names

desmopressin