Donepezil 23mg Tablets
It is used to treat dementia in people with Alzheimer's disease.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Cholinesterase Inhibitor
Pharmacologic Class
Acetylcholinesterase Inhibitor
Pregnancy Category
C
FDA Approved
Jul 2010
DEA Schedule
Not Controlled
Overview
What is this medicine?
Donepezil is a medication used to treat Alzheimer's disease. It works by increasing a natural substance in the brain (acetylcholine) that is important for memory and thinking. This can help improve memory, awareness, and the ability to perform daily activities in some people with Alzheimer's.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Continue taking the medication as directed by your doctor or healthcare provider, even if you start feeling well. Take the medication at bedtime, with or without food, as you prefer. It's essential to drink plenty of non-caffeinated liquids, unless your doctor advises you to limit your fluid intake. Swallow the medication whole; do not chew, break, or crush it.
Storing and Disposing of Your Medication
Store the medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so by your doctor or pharmacist. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, skip it and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses. If you miss seven consecutive days of medication, contact your doctor for guidance on how to proceed.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Continue taking the medication as directed by your doctor or healthcare provider, even if you start feeling well. Take the medication at bedtime, with or without food, as you prefer. It's essential to drink plenty of non-caffeinated liquids, unless your doctor advises you to limit your fluid intake. Swallow the medication whole; do not chew, break, or crush it.
Storing and Disposing of Your Medication
Store the medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of the reach of children and pets. Dispose of unused or expired medications properly. Do not flush them down the toilet or pour them down the drain unless instructed to do so by your doctor or pharmacist. If you're unsure about the best way to dispose of your medication, consult your pharmacist. You may also want to check if there are drug take-back programs available in your area.
Missing a Dose
If you miss a dose, skip it and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses. If you miss seven consecutive days of medication, contact your doctor for guidance on how to proceed.
Lifestyle & Tips
- Take donepezil exactly as prescribed by your doctor, usually once daily in the evening, just before bedtime. Taking it at bedtime may help reduce some side effects like nausea.
- Swallow the tablet whole; do not crush, chew, or break it.
- If you experience stomach upset, try taking the medication with food.
- Do not stop taking donepezil suddenly without consulting your doctor, as this can worsen symptoms.
- Inform your doctor about all other medications, supplements, and herbal products you are taking to avoid potential drug interactions.
- Be aware of potential side effects like dizziness or fainting, especially when standing up quickly. Use caution when driving or operating machinery until you know how the medication affects you.
Available Forms & Alternatives
Dosing & Administration
Adult Dosing
Standard Dose:
23 mg orally once daily. This dose is typically initiated after patients have been stabilized on Donepezil 10 mg once daily for at least 3 months.
Dose Range:
23 - 23 mg
Condition-Specific Dosing:
moderateToSevereAlzheimers:
23 mg orally once daily, after stabilization on 10 mg/day for at least 3 months.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No dosage adjustment generally required.
Moderate:
No dosage adjustment generally required.
Severe:
Use with caution; monitor for adverse effects. No specific dosage adjustment recommendations are provided in product labeling, but close monitoring is advised.
Dialysis:
Donepezil is not dialyzable. No specific dosage adjustment recommendations are provided, but monitor for adverse effects.
Hepatic Impairment:
Mild:
No dosage adjustment generally required.
Moderate:
Use with caution; monitor for adverse effects. No specific dosage adjustment recommendations are provided in product labeling, but close monitoring is advised.
Severe:
Use with caution; monitor for adverse effects. No specific dosage adjustment recommendations are provided in product labeling, but close monitoring is advised.
Pharmacology
Mechanism of Action
Donepezil is a reversible inhibitor of acetylcholinesterase (AChE), the enzyme responsible for the hydrolysis of acetylcholine. By inhibiting AChE, donepezil increases the concentration of acetylcholine at cholinergic synapses in the central nervous system. This enhancement of cholinergic function is thought to be responsible for its therapeutic effects in Alzheimer's disease, where there is a deficiency of cholinergic neurotransmission.
Pharmacokinetics
Absorption:
Bioavailability:
100%
Tmax:
3-4 hours
FoodEffect:
Food does not affect the rate or extent of absorption.
Distribution:
Vd:
12 L/kg
ProteinBinding:
Approximately 96% (primarily to albumin and alpha1-acid glycoprotein)
CnssPenetration:
Yes
Elimination:
HalfLife:
Approximately 70 hours
Clearance:
Not available (primarily hepatic metabolism and renal excretion)
ExcretionRoute:
Urine (approximately 57%), Feces (approximately 15%)
Unchanged:
Approximately 17% (in urine)
Pharmacodynamics
OnsetOfAction:
Within 1-3 weeks (clinical effect)
PeakEffect:
Not precisely defined for cognitive improvement, but steady-state plasma concentrations are reached within 15 days.
DurationOfAction:
24 hours (due to long half-life, allowing once-daily dosing)
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Attention Immediately
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you experience any of the following symptoms, contact your doctor or seek medical help right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Slow heartbeat
Abnormal heartbeat
Difficulty urinating
Seizures
Severe stomach pain
Heartburn
Vomiting blood or coffee ground-like material
Black, tarry, or bloody stools
New or worsening trouble breathing
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people may not experience any side effects or may only have mild ones. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness, fatigue, or weakness
Diarrhea, upset stomach, or vomiting
Trouble sleeping
Muscle cramps
Decreased appetite
Weight loss
Headache
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you experience any of the following symptoms, contact your doctor or seek medical help right away:
Signs of an allergic reaction, such as:
+ Rash
+ Hives
+ Itching
+ Red, swollen, blistered, or peeling skin with or without fever
+ Wheezing
+ Tightness in the chest or throat
+ Trouble breathing, swallowing, or talking
+ Unusual hoarseness
+ Swelling of the mouth, face, lips, tongue, or throat
Severe dizziness or fainting
Slow heartbeat
Abnormal heartbeat
Difficulty urinating
Seizures
Severe stomach pain
Heartburn
Vomiting blood or coffee ground-like material
Black, tarry, or bloody stools
New or worsening trouble breathing
Other Possible Side Effects
Like all medications, this drug can cause side effects. Many people may not experience any side effects or may only have mild ones. If you experience any of the following side effects or any other symptoms that bother you or do not go away, contact your doctor:
Dizziness, fatigue, or weakness
Diarrhea, upset stomach, or vomiting
Trouble sleeping
Muscle cramps
Decreased appetite
Weight loss
Headache
Reporting Side Effects
This list is not exhaustive, and you may experience other side effects. If you have questions or concerns about side effects, contact your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Seek Immediate Medical Attention If You Experience:
- Severe or persistent nausea, vomiting, or diarrhea
- New or worsening stomach pain, heartburn, or dark/bloody stools (signs of stomach ulcer or bleeding)
- Slow or irregular heartbeat, dizziness, lightheadedness, or fainting (syncope)
- New or worsening muscle cramps or weakness
- Difficulty urinating
- Seizures
- Signs of liver problems (e.g., yellowing of skin/eyes, dark urine, persistent nausea/vomiting)
Before Using This Medicine
Before Taking This Medication: Important Information to Share with Your Doctor
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This information will help your doctor and pharmacist assess potential interactions between this medication and other substances you are taking.
* Any existing health problems, as this medication may interact with certain conditions.
To ensure your safety, it is crucial to verify that it is safe to take this medication with all your current medications and health conditions. Never start, stop, or adjust the dose of any medication without first consulting your doctor.
It is essential to inform your doctor about the following:
Any allergies you have, including allergies to this medication, its components, or other substances, such as foods or drugs. Be sure to describe the symptoms you experienced as a result of the allergy.
All medications you are currently taking, including prescription and over-the-counter (OTC) drugs, natural products, and vitamins. This information will help your doctor and pharmacist assess potential interactions between this medication and other substances you are taking.
* Any existing health problems, as this medication may interact with certain conditions.
To ensure your safety, it is crucial to verify that it is safe to take this medication with all your current medications and health conditions. Never start, stop, or adjust the dose of any medication without first consulting your doctor.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. This drug does not cure Alzheimer's disease, and you should continue to receive regular care from your doctor. If you are pregnant, planning to become pregnant, or are breast-feeding, be sure to discuss this with your doctor, as you will need to carefully weigh the benefits and risks of this medication to both you and your baby.
Overdose Information
Overdose Symptoms:
- Severe nausea
- Vomiting
- Salivation (excessive drooling)
- Sweating
- Bradycardia (slow heartbeat)
- Hypotension (low blood pressure)
- Respiratory depression (slow or shallow breathing)
- Collapse
- Convulsions
- Increased muscle weakness (may be fatal if respiratory muscles are involved)
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment may involve atropine sulfate as an antidote.
Drug Interactions
Major Interactions
- Anticholinergics (e.g., atropine, scopolamine, benztropine): May antagonize the effects of donepezil.
- Succinylcholine, other neuromuscular blocking agents: Donepezil may exaggerate neuromuscular blockade.
Moderate Interactions
- Beta-blockers (e.g., metoprolol, carvedilol): Increased risk of bradycardia and syncope.
- NSAIDs (e.g., ibuprofen, naproxen): Increased risk of gastrointestinal bleeding and peptic ulcers.
- CYP2D6 inhibitors (e.g., quinidine, fluoxetine, paroxetine): May increase donepezil plasma concentrations.
- CYP3A4 inhibitors (e.g., ketoconazole, erythromycin, ritonavir): May increase donepezil plasma concentrations.
- CYP2D6 inducers (e.g., rifampin, phenytoin, carbamazepine): May decrease donepezil plasma concentrations.
- CYP3A4 inducers (e.g., rifampin, phenytoin, carbamazepine): May decrease donepezil plasma concentrations.
Monitoring
Baseline Monitoring
Cognitive function assessment (e.g., MMSE, ADAS-Cog)
Rationale: To establish baseline cognitive status and track disease progression/response to treatment.
Timing: Prior to initiation of therapy.
Heart rate and rhythm (ECG if clinically indicated)
Rationale: Donepezil can cause bradycardia and syncope due to its cholinergic effects.
Timing: Prior to initiation, especially in patients with pre-existing cardiac conditions.
Gastrointestinal symptoms assessment
Rationale: To assess for baseline GI issues (e.g., peptic ulcer disease, history of GI bleeding) which may be exacerbated.
Timing: Prior to initiation.
Routine Monitoring
Cognitive function assessment
Frequency: Every 6-12 months, or as clinically indicated.
Target: Improvement or stabilization of cognitive scores.
Action Threshold: Significant decline may warrant re-evaluation of treatment.
Heart rate and blood pressure
Frequency: Periodically, or if symptoms of bradycardia/syncope occur.
Target: Within normal limits for the patient.
Action Threshold: Symptomatic bradycardia (<50 bpm) or syncope requires immediate medical attention and dose re-evaluation.
Gastrointestinal symptoms (nausea, vomiting, diarrhea, dyspepsia)
Frequency: Regularly, especially during dose titration and initial months.
Target: Minimal to no symptoms.
Action Threshold: Persistent or severe symptoms may require dose reduction or discontinuation.
Weight
Frequency: Periodically
Target: Stable weight
Action Threshold: Significant unexplained weight loss may indicate underlying issues or severe GI side effects.
Symptom Monitoring
- Nausea
- Vomiting
- Diarrhea
- Dyspepsia
- Anorexia
- Muscle cramps
- Fatigue
- Insomnia
- Dizziness
- Headache
- Syncope
- Bradycardia
- Urinary incontinence
- Seizures (rare)
Special Patient Groups
Pregnancy
Donepezil is Pregnancy Category C. There are no adequate and well-controlled studies in pregnant women. Use during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Potential for adverse effects on fetal development, though human data are limited.
Second Trimester:
Limited data; potential for adverse effects.
Third Trimester:
Limited data; potential for adverse effects, including cholinergic effects on the neonate.
Lactation
Donepezil is excreted in the milk of rats. It is not known whether donepezil is excreted in human milk. Due to the potential for serious adverse reactions in breastfed infants, a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.
Infant Risk:
Potential for cholinergic effects (e.g., bradycardia, vomiting, diarrhea) in the infant. Risk is considered moderate (L3).
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Donepezil is not indicated for use in children.
Geriatric Use
Donepezil is primarily used in the geriatric population. No specific dosage adjustment is required based solely on age. However, elderly patients may be more susceptible to cholinergic side effects (e.g., bradycardia, syncope, GI upset), requiring careful monitoring.
Clinical Information
Clinical Pearls
- Donepezil 23 mg is a higher dose intended for patients with moderate to severe Alzheimer's disease who have been stabilized on Donepezil 10 mg for at least 3 months. It is not for initial therapy.
- The 23 mg dose may offer modest additional cognitive benefits but is associated with a higher incidence of gastrointestinal adverse events (nausea, vomiting, diarrhea) compared to the 10 mg dose.
- Administer donepezil in the evening, just prior to bedtime, to help mitigate some side effects like nausea and dizziness.
- Monitor patients for signs of bradycardia, syncope, and GI bleeding, especially those with pre-existing cardiac conditions or a history of peptic ulcer disease/NSAID use.
- Educate caregivers on the importance of consistent dosing and monitoring for adverse effects, as patients with Alzheimer's may not be able to report symptoms reliably.
Alternative Therapies
- Rivastigmine (Exelon) - another acetylcholinesterase inhibitor (oral, patch)
- Galantamine (Razadyne) - another acetylcholinesterase inhibitor (oral)
- Memantine (Namenda) - NMDA receptor antagonist (often used in combination with cholinesterase inhibitors for moderate to severe AD)
Cost & Coverage
Average Cost:
$100 - $300 per 30 tablets (generic 23mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 (Generic) or Tier 2 (Brand, if preferred)
General Drug Facts
If your symptoms or health issues persist or worsen, it's essential to contact your doctor for further guidance. To ensure your safety, never share your medication with others or take someone else's medication. Some medications may come with an additional patient information leaflet, so be sure to check with your pharmacist for more information. If you have any questions or concerns about your medication, don't hesitate to reach out to your doctor, nurse, pharmacist, or other healthcare provider. In the event of a suspected overdose, immediately call your local poison control center or seek medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.