From the Guidelines
Oxybutynin can cause several side effects due to its anticholinergic properties, including dry mouth, constipation, blurred vision, drowsiness, and urinary retention, as well as cognitive side effects in elderly patients, such as confusion, memory problems, and hallucinations, as noted in a 2021 study on polypharmacy management in older patients 1.
Common Side Effects
- Dry mouth (occurring in up to 70% of patients)
- Constipation
- Blurred vision
- Drowsiness
- Urinary retention
- Headaches
- Dizziness
- Gastrointestinal disturbances like nausea ### Less Common but Serious Side Effects
- Cognitive side effects in elderly patients, including confusion, memory problems, and hallucinations
- Tachycardia (increased heart rate)
- Worsening of symptoms of glaucoma, gastroesophageal reflux disease, and prostatic hyperplasia ### Special Considerations
- Elderly patients are especially susceptible to cognitive side effects
- The extended-release formulation or transdermal patch may cause fewer side effects than immediate-release tablets
- Patients should consult their healthcare provider if experiencing troublesome side effects, rather than discontinuing the medication abruptly, as advised in a 2012 guideline on the diagnosis and treatment of overactive bladder (non-neurogenic) in adults 2.
Management of Side Effects
- Patients taking oxybutynin should be monitored for signs of anticholinergic burden, which can adversely affect cognition and functionality, as noted in a 2021 study on polypharmacy management in older patients 1.
- Healthcare providers should consider the potential risks and benefits of oxybutynin in older patients, particularly those with a history of cognitive impairment or other conditions that may be exacerbated by anticholinergic medications, as discussed in a 2021 article on polypharmacy management in older patients 3.
From the FDA Drug Label
The safety and efficacy of oxybutynin chloride was evaluated in a total of 199 patients in three clinical trials. These participants were treated with oxybutynin chloride 5-20 mg/day for up to 6 weeks. Table 3 shows the incidence of adverse events judged by investigators to be at least possibly related to treatment and reported by at least 5% of patients Table 3 Incidence (%) of Adverse Events Reported by ≥ 5% of Patients Using Oxybutynin Chloride (5-20 mg/day) Body System Adverse Event Oxybutynin Chloride (5-20 mg/day) (n=199) Infections and Infestations Urinary tract infection 6.5% Psychiatric Disorders Insomnia Nervousness 5.5% 6.5% Nervous System Disorders Dizziness Somnolence Headache 16.6% 14.0% 7.5% Eye Disorders Blurred vision 9. 6% Gastrointestinal Disorders Dry mouth Constipation Nausea Dyspeza 71.4% 15.1% 11.6% 6.0% Renal and Urinary Disorders Urinary Hesitation Urinary Retention 8.5% 6. 0%
The side effects of Oxybutynin (Ditropan) include:
- Common side effects: + Dry mouth (71.4%) + Dizziness (16.6%) + Somnolence (14.0%) + Urinary tract infection (6.5%) + Nervousness (6.5%) + Insomnia (5.5%) + Constipation (15.1%) + Nausea (11.6%) + Blurred vision (9.6%) + Urinary hesitation (8.5%) + Urinary retention (6.0%)
- Less common side effects (reported by 1 to <5% of patients): + Respiratory, Thoracic and Mediastinal Disorders: nasal dryness, cough, pharyngolaryngeal pain, dry throat, sinus congestion, hoarseness, asthma, nasal congestion + Gastrointestinal Disorders: diarrhea, abdominal pain, loose stools, flatulence, vomiting, abdominal pain upper, dysphagia, aptyalism, eructation, tongue coated + Skin and Subcutaneous Tissue Disorders: dry skin, pruritis + Musculoskeletal and Connective Tissue Disorders: back pain, arthralgia, pain in extremity, flank pain + Renal and Urinary Disorders: dysuria, pollakiuria + General Disorders and Administration Site Conditions: fatigue, edema peripheral, asthenia, pain, thirst, edema + Investigations: blood pressure increased, blood glucose increased, blood pressure decreased + Injury, Poisoning, and Procedural Complications: fall 4
From the Research
Side Effects of Oxybutynin (Ditropan)
- Adverse effects related to the anticholinergic activity of oxybutynin occur frequently and can be sufficiently troublesome to necessitate treatment discontinuation in up to 25% of patients, depending on the dosage 5
- Common side effects include: + Dry mouth + Constipation + Blurred vision
- Increases in residual urine volume suggesting urinary retention can also develop in some oxybutynin recipients 5
- Transdermal oxybutynin is well tolerated in clinical trials, with application site reactions being the most common adverse effect, although the majority are mild to moderate in severity 6, 7, 8
- Anticholinergic side effects such as dry mouth are less frequently reported in patients treated with transdermal oxybutynin than in those receiving orally administered oxybutynin or tolterodine 6, 7
- Skin reactions occur frequently with transdermal oxybutynin, necessitating changes of application site 8