From the Guidelines
Oxybutynin can be used for the treatment of nocturnal enuresis, but only in children who have failed standard treatment and after nonpharmacological methods have been tried. According to the international children's continence society, oxybutynin is one of the anticholinergic drugs with reasonable documentation of efficacy and safety in childhood, along with tolterodine and propiverine 1.
Key Considerations
Before considering oxybutynin for nocturnal enuresis, several factors should be taken into account:
- Nonpharmacological methods to decrease detrusor overactivity should be tried first, such as instituting sound, regular voiding habits.
- Constipation should be excluded or treated.
- Post-void residual urine, dysfunctional voiding, or low voiding frequency should be excluded, which requires a frequency-volume chart and uroflowmetry with ultrasound measurement of post-void residual urine.
Treatment Details
The usual dose of oxybutynin is 5 mg at bedtime, which may need to be doubled if necessary 1. The anti-enuretic effect should appear within a maximum of 2 months. Combination treatment with desmopressin at a standard dose may also be needed.
Side Effects
The most bothersome side effect of oxybutynin is constipation, which may be heralded by a slowly decreasing anti-enuretic effect, while the greatest danger is that post-void residual urine may cause UTIs 1. Mood changes are also a potential side effect, although this seems to be uncommon when alternatives other than oxybutynin are chosen.
Monitoring and Follow-up
Regular reassessment is necessary to evaluate the effectiveness of oxybutynin and manage potential side effects. The child must maintain sound voiding habits, and the family must react if the child has dysuria or unexplained fever.
From the Research
Oxybutynin for Nocturnal Enuresis
- Oxybutynin can be used in combination with desmopressin for the treatment of nocturnal enuresis, especially in cases where desmopressin alone is not effective 2, 3, 4.
- The combination of oxybutynin and desmopressin has been shown to improve response rates compared to desmopressin alone, with response rates ranging from 68% to 96.7% 2, 3, 4.
- Predictive factors for response to combination therapy include nocturnal polyuria and absence of constipation 3.
- Oxybutynin can be used in escalating doses in combination with desmopressin to achieve optimal response, with doses ranging from 5mg to 10mg 2.
- Combination therapy with oxybutynin and desmopressin is generally well-tolerated, with no significant adverse events or side effects reported in most studies 2, 3, 4.
Comparison with Other Treatments
- Oxybutynin in combination with desmopressin has been compared to imipramine in combination with desmopressin, with some studies suggesting that imipramine may be more effective in reducing wet nights 5, 6.
- However, oxybutynin is still considered a safe and effective treatment option for nocturnal enuresis, especially in cases where imipramine is not tolerated or is contraindicated 2, 3, 4.
Clinical Implications
- Oxybutynin can be considered as an adjunct therapy to desmopressin in patients with nocturnal enuresis who do not respond to desmopressin alone 2, 3, 4.
- Clinicians should carefully evaluate the patient's response to treatment and adjust the dose of oxybutynin as needed to achieve optimal response 2.
- Further studies are needed to confirm the efficacy and safety of oxybutynin in combination with desmopressin for the treatment of nocturnal enuresis 2, 3, 4.