Oxybutynin with Donepezil Interaction Details
Brand Names Associated with Oxybutynin
- Ditropan®
- Ditropan® XL
- Oxybutynin
Brand Names Associated with Donepezil
- Aricept®
- Aricept® ODT
- Donepezil
- Namzaric®(as a combination product containing Donepezil, Memantine)
Medical Content Editor Dr. Brian Staiger, PharmD
Last updated
Nov 17, 2023
Interaction Effect
Interference with the cholinergic effects of donepezil or the anticholinergic agent effects of oxybutynin; increased risk of seizure
Interaction Summary
Concomitant use of a cholinesterase inhibitor, such as donepezil, and an anticholinergic agent, such as oxybutynin, may result in interference with the efficacy of both agents. Additionally donepezil has been associated with a seizure threshold lowering effect . In a prospective cohort study, a decline in activity of daily living (ADL), but not cognitive function, was reported in higher functioning nursing home patients (with little to no dependence) . Therefore, consider evaluating risks and benefits before giving a cholinesterase inhibitor concomitantly with an anticholinergic and monitor for seizures.
Severity
Major
Onset
Delayed
Evidence
Established
How To Manage Interaction
Concomitant use of a cholinesterase inhibitor, such as donepezil, and an anticholinergic agent, such as oxybutynin, may result in interference with the efficacy of both agents. Additionally donepezil has been associated with a seizure threshold lowering effect . Therefore, consider evaluating risks and benefits before giving a cholinesterase inhibitor concomitantly with an anticholinergic and monitor for seizures.
Mechanism Of Interaction
Cholinergic receptor antagonism by the anticholinergic drug; additive seizure threshold lowering effect
Literature Reports
A) A decline in activity of daily living (ADL), but not cognitive function, was reported in high functioning nursing home patients (with little to no dependence) following concomitant use of oxybutynin or tolterodine and a cholinesterase inhibitor in a prospective, cohort study (N=3536). Patients were at least 65 years of age, had at least 2 consecutive cholinesterase inhibitor prescriptions, and had not received an anticholinergic other than oxybutynin or tolterodine; resulting in 395 patients with concomitant therapy and 3141 cohorts with cholinesterase inhibitor therapy alone. Cholinesterase inhibitors were donepezil (70.5%), rivastigmine (19.9%), galantamine (16.5%). Nearly 11% were concomitantly prescribed oxybutynin (n=164), tolterodine (n=199), or both drugs at different times (n=13). The median duration of dual use was 141 days. Concomitant use of an anticholinergic and a cholinesterase inhibitor resulted in a significant decrease of 0.53 ADL points/quarter in high functioning patients compared with the use of a cholinesterase inhibitor alone . .
B) Case reports describe delirium in three 82-year-old patients (2 men, 1 women) following concomitant use of a cholinesterase inhibitor for Alzheimer's disease and tolterodine for urinary incontinence. In case 1, the patient, who was ambulatory, had been receiving donepezil 5 mg at bedtime for the past 2 months. Within one week after starting tolterodine (dose not specified), he developed sudden delusional and aggressive behavior. Subsequently, donepezil was stopped and within 48 hours, his behavior normalized. In case 2, the patient was stable on rivastigmine 6 mg 2 times per day and had been in an assisted living facility for 3 years. She was initiated on tolterodine (dose not specified) and within 1 week, she developed agitation, anxiety, panic attacks, confusion, delusions. Two 0.5-mg lorazepam doses were given with no improvement. Tolterodine was withdrawn 2 days after lorazepam was discontinued. Her symptoms resolved within 24 hours of discontinuing tolterodine. In case 3, the patient had been receiving donepezil 10 mg/day for 2 years due to dementia. His medical history also included Parkinson's disease. He was initiated on tolterodine 20 mg 2 times/day. Disorientation and confusion occurred within 2 weeks of tolterodine initiation. He was taken to the emergency department where tolterodine was stopped. The patient's symptoms resolved within 24 hours of tolterodine discontinuation .
Oxybutynin Overview
-
Oxybutynin is used to treat overactive bladder (a condition in which the bladder muscles contract uncontrollably and cause frequent urination, urgent need to urinate, and inability to control urination) in certain adults and children. Oxybutynin is also used as an extended-release tablet to control bladder muscles in adults and children 6 years of age and older with spina bifida (a disability that occurs when the spinal cord does not close properly before birth), or other nervous system conditions that affect the bladder muscles. Oxybutynin is in a class of medications called anticholinergics/antimuscarinics. It works by relaxing the bladder muscles.
Donepezil Overview
-
Donepezil is used to treat dementia (a brain disorder that affects the ability to remember, think clearly, communicate, and perform daily activities and may cause changes in mood and personality) in people who have Alzheimer's disease (AD; a brain disease that slowly destroys the memory and the ability to think, learn, communicate and handle daily activities). Donepezil is in a class of medications called cholinesterase inhibitors. It improves mental function (such as memory, attention, the ability to interact with others, speak, think clearly, and perform regular daily activities) by increasing the amount of a certain naturally occurring substance in the brain. Donepezil may improve the ability to think and remember or slow the loss of these abilities in people who have AD. However, donepezil will not cure AD or prevent the loss of mental abilities at some time in the future.
Return To Our Drug Interaction Homepage
Feedback, Question Or Comment About This Information?
Ask Dr. Brian Staiger, PharmD, our medical editor, directly! He's always more than happy to assist.
Definitions
Severity Categories
Contraindicated
These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.
Major
This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.
Moderate
This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.
Minor
While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.
Onset
Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.
Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.
Evidence
Level of documentation of the interaction.
Established: The interaction is documented and substantiated in peer-reviewed medical literature.
Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.
How To Manage The Interaction
Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.
It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.
Mechanism Of Interaction
The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.
Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.
Where Does Our Information Come From?
Information for our drug interactions is compiled from several drug compendia, including:
The prescribing information for each drug, as published on DailyMED, is also used.
Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.
The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.