DESMOPRESSIN ACETATE 0.2MG TABLETS 30`S

DESMOPRESSIN is a synthetic analogue of arginine vasopressin (AVP), the body's natural antidiuretic hormone (ADH). Desmopressin acts on V2 receptors in the kidney collecting ducts, increasing water reabsorption and reducing urine output without the vasopressor (blood pressure raising) effects of natural vasopressin.

Desmopressin 0.2 mg tablets are indicated for:

·       primary nocturnal enuresis (bedwetting) in children and adults;

·       central diabetes insipidus — a condition caused by insufficient ADH production from the pituitary gland, resulting in the production of large volumes of dilute urine;

·       polyuria/polydipsia associated with central (not nephrogenic) diabetes insipidus.

In von Willebrand disease type 1 and mild haemophilia A, desmopressin transiently releases stored von Willebrand factor and factor VIII from endothelial cells, helping to control minor bleeding. (This is typically managed with IV or intranasal formulations rather than the tablet form.)

Nocturnal Enuresis (Bedwetting)

•       Children (5 years and above) and adults: 0.1 mg (1 tablet) taken 1 hour before bedtime.

Central Diabetes Insipidus

•       Initial: 0.05 to 0.2 mg once daily at bedtime.

•       May adjust bedtime dosage in 0.05 mg increments, if needed, to control nocturia, up to 1.2 mg/day administered in 2 or 3 divided doses.

Important Administration Instructions

Tablets should be swallowed whole with water. For nocturnal enuresis, fluid intake must be restricted from 1 hour before taking the dose until 8 hours after — this is essential to prevent dangerous hyponatraemia (low sodium). Drink only small sips of water with the tablet.

Common Side Effects

•       Headache.

•       Nausea and abdominal discomfort.

•       Nasal congestion (more common with intranasal forms).

Serious Side Effect — Hyponatraemia (Low Blood Sodium)

The most important and potentially dangerous side effect is hyponatraemia (low serum sodium), caused by excessive water retention. This is especially likely if fluid restriction is not observed. Symptoms include:

•       Headache, nausea, vomiting.

•       Confusion, irritability, drowsiness.

•       Seizures or loss of consciousness (severe cases — medical emergency).

If symptoms of hyponatraemia occur, stop desmopressin immediately and seek urgent medical attention.

Fluid Restriction is Mandatory

For nocturnal enuresis, patients must not drink more than 240 mL (one glass) from 1 hour before the dose until 8 hours after. Non-adherence to this rule is the primary cause of dangerous hyponatraemia. Parents/caregivers must be thoroughly counselled on this restriction.

Electrolyte Monitoring

Measure serum sodium before starting therapy and at regular intervals during treatment, especially in elderly patients, young children, and those with conditions predisposing to electrolyte disturbance. If serum sodium falls below 130 mmol/L, stop treatment and restrict fluids.

Elderly Patients

Older adults are particularly vulnerable to hyponatraemia due to reduced renal concentrating ability and often higher fluid intake. Extra caution and more frequent electrolyte monitoring is required in this population.

Intercurrent Illness

During acute illness (especially with vomiting, diarrhoea, or fever), desmopressin therapy should be temporarily suspended and fluid management reviewed, as electrolyte disturbances are more likely.

•       Non-steroidal anti-inflammatory drugs (NSAIDs — ibuprofen, diclofenac) — enhance antidiuretic effect and increase risk of hyponatraemia; use with caution.

•       Tricyclic antidepressants (e.g., imipramine, amitriptyline) — increase antidiuretic effect.

•       Carbamazepine, chlorpropamide — potentiate antidiuretic effect; increased hyponatraemia risk.

•       Loperamide — increases desmopressin plasma levels by approximately threefold; dose adjustment may be needed.

•       Indomethacin — increases renal sensitivity to desmopressin.

•       Diuretics — may antagonise the antidiuretic effect.

•       Store below 30 degrees Celsius.

•       Keep dry — protect from moisture.

•       Keep in original blister packaging.

•       Keep out of reach of children.

•       Do not use after the expiry date printed on the pack.

Desmopressin 0.2 mg tablets are a prescription-only medicine (POM) in Kenya, available through authorised pharmacies with a valid prescription from a registered medical practitioner.

It is used across general practice, paediatrics, endocrinology, and nephrology settings.

Electrolyte Monitoring Schedule

•       Serum sodium: before initiation, at 7 days, 1 month, then 3-monthly during chronic therapy.

•       Action threshold: discontinue if Na+ falls below 130 mmol/L.

•       More frequent monitoring in the elderly (monthly), young children, and patients on concomitant NSAIDs or antidepressants.

Treatment Withdrawal 

After 3 months of treatment, assess dry night frequency. If successful, gradually taper and trial off. Reassess after a 1-week washout. If dryness is maintained, discontinue. If bedwetting recurs, reinstate for a further 3 months, then repeat assessment.

Paediatric Counselling Key Points

Counsel parents explicitly on the fluid restriction rule, document this counselling. Advise limiting fluid intake after 5 pm. Provide a written information sheet. Ensure alarm bells are used adjunctively when possible for enuresis.

Diabetes Insipidus Titration

Start low (0.1 mg twice or three times daily) and titrate based on 24-hour urine volume and osmolality. Target: urine osmolality >300 mOsm/kg. Avoid over-suppression (risk of hyponatraemia); accept some polyuria if electrolytes are marginal.

How long will my child need to take this medicine for bedwetting?

Treatment is usually given for 3 months at a time. After that, your doctor will review whether it is still needed. Some children achieve lasting dryness after one course; others may need longer treatment. The medicine is not a permanent cure, but helps control the problem while the child matures.

Can my child drink normally during the day while on this medicine?

Yes — normal daytime fluid intake is encouraged and important for hydration. The restriction only applies from 1 hour before the bedtime dose until the next morning (8 hours). During the day, drinks should be unrestricted.

What happens if I forget to restrict fluids before the bedtime dose?

If fluid intake is not restricted, there is a risk of water retention and dangerously low blood sodium (hyponatraemia). If this occurs, symptoms include headache, confusion, and in severe cases, seizures. On any night where fluid restriction is not possible, it is safer to skip the dose and take it the next night.