Artane 5mg Tablets
It is used to treat Parkinson's disease.It is used to treat side effects caused by some other drugs.
Drug Class
Antiparkinsonian agent
Pharmacologic Class
Anticholinergic, Muscarinic Antagonist
Pregnancy Category
Category C
FDA Approved
Jan 1970
DEA Schedule
Not Controlled
Overview
What is this medicine?
Trihexyphenidyl is a medication used to help control muscle stiffness, tremors, and other involuntary movements often associated with Parkinson's disease or side effects from certain psychiatric medications. It works by balancing certain natural substances in the brain.
How to Use This Medicine
Taking Your Medication
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication as directed, with or without food. If you experience stomach upset, taking it with food may help. Stay hydrated by drinking plenty of non-caffeinated liquids, unless your doctor advises you to limit your fluid intake.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of 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. If you have questions about disposing 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, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
To use this medication correctly, follow your doctor's instructions and read all the information provided. Take your medication as directed, with or without food. If you experience stomach upset, taking it with food may help. Stay hydrated by drinking plenty of non-caffeinated liquids, unless your doctor advises you to limit your fluid intake.
Storing and Disposing of Your Medication
Store your medication at room temperature in a dry location, avoiding the bathroom. Keep all medications in a safe place, out of 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. If you have questions about disposing 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, take it as soon as you remember. However, if it's close to the time for your next scheduled dose, skip the missed dose and resume your regular dosing schedule. Do not take two doses at the same time or take extra doses to make up for a missed one.
Lifestyle & Tips
- Take with food if stomach upset occurs.
- Do not stop taking this medication suddenly without consulting your doctor, as it can worsen symptoms.
- Avoid activities requiring mental alertness, such as driving or operating machinery, until you know how this medication affects you, as it can cause dizziness or blurred vision.
- Avoid alcohol and other CNS depressants, as they can increase drowsiness.
- Stay hydrated and avoid overheating, especially in hot weather or during exercise, as this medication can reduce sweating and increase the risk of heat stroke.
- Manage constipation by increasing fiber intake, fluids, and exercise, or with laxatives as directed by your doctor.
- Report any difficulty urinating to your doctor.
Available Forms & Alternatives
Available Strengths:
Generic Alternatives:
Dosing & Administration
Adult Dosing
Standard Dose:
2 mg orally 3 times daily
Dose Range:
1 - 15 mg
Condition-Specific Dosing:
Parkinsonism:
Initial: 1 mg orally on day 1, then 2 mg on day 2. Increase by 2 mg/day every 3-5 days until optimal response. Maintenance: 6-10 mg/day in 3-4 divided doses, with meals. Max: 15 mg/day.
Drug-induced extrapyramidal symptoms:
Initial: 1 mg orally. If symptoms not controlled, increase to 5-15 mg/day in divided doses. Often 5-10 mg/day is sufficient.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established (safety and efficacy not established in children)
Adolescent:
Not established (safety and efficacy not established in adolescents)
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment, use with caution
Moderate:
Use with caution, consider lower initial doses and slower titration due to potential for accumulation of drug and metabolites.
Severe:
Use with caution, consider significant dose reduction (e.g., 50% or more) and extended dosing intervals. Monitor closely for adverse effects.
Dialysis:
Not well studied. Likely not dialyzable due to high volume of distribution. Use with extreme caution, significant dose reduction may be necessary.
Hepatic Impairment:
Mild:
No specific adjustment, use with caution
Moderate:
Use with caution, consider lower initial doses and slower titration due to hepatic metabolism.
Severe:
Use with caution, consider significant dose reduction. Monitor closely for adverse effects.
Confidence:
Medium
Pharmacology
Mechanism of Action
Trihexyphenidyl is a synthetic tertiary amine anticholinergic agent. It acts as a muscarinic acetylcholine receptor antagonist, primarily blocking M1 receptors in the central nervous system (CNS). In Parkinson's disease, it helps to restore the balance between cholinergic and dopaminergic activity in the basal ganglia, thereby reducing tremor and rigidity. It also has some direct relaxant effect on smooth muscle.
Pharmacokinetics
Absorption:
Bioavailability:
Well absorbed orally, but specific percentage not well quantified.
Tmax:
Approximately 1-2 hours
FoodEffect:
Food may delay absorption but does not significantly affect the extent of absorption. Taking with food may reduce gastrointestinal upset.
Distribution:
Vd:
Large volume of distribution (not precisely quantified, but indicates extensive tissue distribution)
ProteinBinding:
Not extensively documented, but generally considered low to moderate.
CnssPenetration:
Yes (readily crosses the blood-brain barrier)
Elimination:
HalfLife:
Approximately 6-10 hours (variable)
Clearance:
Not precisely quantified
ExcretionRoute:
Primarily renal (as unchanged drug and metabolites)
Unchanged:
Significant portion excreted unchanged in urine (up to 50% in some studies)
Pharmacodynamics
OnsetOfAction:
Within 1 hour
PeakEffect:
2-3 hours
DurationOfAction:
6-12 hours
Confidence:
Medium
Safety & Warnings
Side Effects
Urgent Side Effects: Seek Medical Help Right Away
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
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
Hallucinations (seeing or hearing things that are not there)
Feeling agitated or experiencing a change in behavior
Confusion or memory problems
Trouble passing urine
Rapid heartbeat
Severe constipation or stomach pain, which may be signs of a severe bowel problem
Muscle weakness
New or worsening trouble controlling body movements
Changes in eyesight, eye pain, or severe eye irritation
Fever
Inability to sweat during physical activity or in warm temperatures
Enlarged pupils
Neuroleptic malignant syndrome (NMS), a rare but potentially life-threatening condition that can occur when this medication is stopped suddenly or the dose is lowered. Symptoms of NMS include:
+ Fever
+ Muscle cramps or stiffness
+ Dizziness
+ Severe headache
+ Confusion
+ Changes in thinking
+ Rapid or abnormal heartbeat
+ Excessive sweating
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. 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 or drowsiness
Upset stomach or vomiting
Constipation
Headache
Dry mouth
Feeling nervous or excitable
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult your doctor. You can also report side effects to the FDA at 1-800-332-1088 or online at https://www.fda.gov/medwatch.
Although rare, some people may experience severe and potentially life-threatening side effects while taking this medication. If you notice any of the following symptoms, contact your doctor or seek medical attention immediately:
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
Hallucinations (seeing or hearing things that are not there)
Feeling agitated or experiencing a change in behavior
Confusion or memory problems
Trouble passing urine
Rapid heartbeat
Severe constipation or stomach pain, which may be signs of a severe bowel problem
Muscle weakness
New or worsening trouble controlling body movements
Changes in eyesight, eye pain, or severe eye irritation
Fever
Inability to sweat during physical activity or in warm temperatures
Enlarged pupils
Neuroleptic malignant syndrome (NMS), a rare but potentially life-threatening condition that can occur when this medication is stopped suddenly or the dose is lowered. Symptoms of NMS include:
+ Fever
+ Muscle cramps or stiffness
+ Dizziness
+ Severe headache
+ Confusion
+ Changes in thinking
+ Rapid or abnormal heartbeat
+ Excessive sweating
Other Possible Side Effects
Like all medications, this drug can cause side effects. While many people may not experience any side effects or only minor ones, it's essential to discuss any concerns with your doctor. 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 or drowsiness
Upset stomach or vomiting
Constipation
Headache
Dry mouth
Feeling nervous or excitable
This is not an exhaustive list of possible side effects. If you have questions or concerns about side effects, consult 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 confusion or disorientation
- Hallucinations (seeing or hearing things that are not there)
- Severe blurred vision or eye pain
- Difficulty urinating or inability to urinate
- Severe constipation
- Rapid or irregular heartbeat
- Signs of heat stroke (e.g., fever, hot dry skin, confusion, rapid pulse)
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 allergic reaction you experienced, including any symptoms that occurred.
If you have been diagnosed with narrow-angle glaucoma, a condition that affects the eyes.
* If you have a history of tardive dyskinesia, a severe muscle disorder.
This list is not exhaustive, and it is crucial to discuss all your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. Additionally, share any health problems you have, as they may interact with this medication.
To ensure your safety, always check with your doctor before starting, stopping, or changing the dose of any medication. This will help prevent potential interactions and ensure that it is safe for you to take this medication with your other drugs and health conditions.
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 allergic reaction you experienced, including any symptoms that occurred.
If you have been diagnosed with narrow-angle glaucoma, a condition that affects the eyes.
* If you have a history of tardive dyskinesia, a severe muscle disorder.
This list is not exhaustive, and it is crucial to discuss all your medications, including prescription and over-the-counter drugs, natural products, and vitamins, with your doctor and pharmacist. Additionally, share any health problems you have, as they may interact with this medication.
To ensure your safety, always check with your doctor before starting, stopping, or changing the dose of any medication. This will help prevent potential interactions and ensure that it is safe for you to take this medication with your other drugs and health conditions.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication.
Before operating a vehicle or engaging in any activity that requires your full attention, wait until you understand how this medication affects you. It is also crucial to discuss the use of alcohol, marijuana, or other forms of cannabis, as well as prescription or over-the-counter (OTC) medications that may cause drowsiness, with your doctor beforehand.
Do not abruptly discontinue this medication without first consulting your doctor, as this may increase your risk of experiencing side effects. If you need to stop taking this drug, your doctor will provide guidance on how to gradually taper off the medication to minimize potential risks.
Individuals with narrow-angle glaucoma should be aware that this medication has been associated with vision loss. It is vital to consult with your doctor about this potential risk. Additionally, adhere to your doctor's recommendations for regular eye pressure and vision checks.
There is a risk of heat stroke associated with this medication, particularly in hot weather or during physical activity. Therefore, it is crucial to exercise caution and stay hydrated. If you are 60 years or older, use this medication with caution, as you may be more susceptible to side effects.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. It is essential to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision.
Before operating a vehicle or engaging in any activity that requires your full attention, wait until you understand how this medication affects you. It is also crucial to discuss the use of alcohol, marijuana, or other forms of cannabis, as well as prescription or over-the-counter (OTC) medications that may cause drowsiness, with your doctor beforehand.
Do not abruptly discontinue this medication without first consulting your doctor, as this may increase your risk of experiencing side effects. If you need to stop taking this drug, your doctor will provide guidance on how to gradually taper off the medication to minimize potential risks.
Individuals with narrow-angle glaucoma should be aware that this medication has been associated with vision loss. It is vital to consult with your doctor about this potential risk. Additionally, adhere to your doctor's recommendations for regular eye pressure and vision checks.
There is a risk of heat stroke associated with this medication, particularly in hot weather or during physical activity. Therefore, it is crucial to exercise caution and stay hydrated. If you are 60 years or older, use this medication with caution, as you may be more susceptible to side effects.
If you are pregnant, planning to become pregnant, or breastfeeding, inform your doctor. It is essential to discuss the potential benefits and risks of this medication to both you and your baby to make an informed decision.
Overdose Information
Overdose Symptoms:
- Exaggerated anticholinergic effects (e.g., dilated pupils, blurred vision, hot dry skin, flushed face, dry mucous membranes, difficulty swallowing)
- CNS effects (e.g., confusion, disorientation, agitation, hallucinations, delirium, psychosis, seizures, coma)
- Cardiovascular effects (e.g., tachycardia, arrhythmias, hypertension followed by hypotension)
- Respiratory depression
- Urinary retention
- Paralytic ileus
What to Do:
Seek immediate medical attention. Call 911 or Poison Control at 1-800-222-1222. Treatment is supportive and symptomatic. Physostigmine may be used as an antidote in severe cases.
Drug Interactions
Contraindicated Interactions
- Narrow-angle glaucoma (absolute contraindication)
- Myasthenia gravis (relative contraindication, may worsen muscle weakness)
Major Interactions
- Other anticholinergic drugs (e.g., atropine, scopolamine, benztropine, tricyclic antidepressants, phenothiazines, antihistamines with anticholinergic effects like diphenhydramine): Additive anticholinergic effects (e.g., dry mouth, blurred vision, urinary retention, constipation, confusion, hallucinations, heat stroke).
- CNS depressants (e.g., alcohol, opioids, benzodiazepines, sedatives): Additive CNS depression (e.g., sedation, dizziness, impaired coordination).
- Phenothiazines (e.g., chlorpromazine, thioridazine): May reduce the antipsychotic efficacy of phenothiazines and increase the risk of anticholinergic side effects. May also increase the risk of tardive dyskinesia.
Moderate Interactions
- Digoxin: Anticholinergics may increase digoxin absorption, potentially leading to increased digoxin levels.
- Antacids: May reduce the absorption of trihexyphenidyl if given concurrently. Separate administration by at least 2 hours.
- Metoclopramide: Anticholinergics antagonize the prokinetic effects of metoclopramide.
- Potassium chloride (oral solid dosage forms): Increased risk of gastrointestinal lesions due to delayed gastric emptying.
Minor Interactions
- None specifically cited as minor, but general caution with any drug that affects GI motility or CNS.
Monitoring
Baseline Monitoring
Ophthalmic examination (including intraocular pressure)
Rationale: To rule out narrow-angle glaucoma, which is a contraindication.
Timing: Prior to initiation
Baseline mental status assessment
Rationale: To establish a baseline for monitoring cognitive side effects, especially in elderly patients.
Timing: Prior to initiation
Urinary function assessment (e.g., history of benign prostatic hyperplasia)
Rationale: To assess risk of urinary retention.
Timing: Prior to initiation
Routine Monitoring
Anticholinergic side effects (e.g., dry mouth, blurred vision, constipation, urinary retention)
Frequency: Regularly, especially during dose titration and long-term therapy
Target: Minimize severity
Action Threshold: If severe or intolerable, consider dose reduction or discontinuation.
Mental status (e.g., confusion, disorientation, hallucinations)
Frequency: Regularly, especially in elderly patients or those with cognitive impairment
Target: Maintain baseline cognitive function
Action Threshold: If new or worsening cognitive impairment, reduce dose or discontinue.
Intraocular pressure (for patients at risk of glaucoma)
Frequency: Periodically, as clinically indicated
Target: Normal range
Action Threshold: If elevated, consult ophthalmologist and consider alternative therapy.
Gastrointestinal function (e.g., bowel movements)
Frequency: Regularly
Target: Regular bowel movements
Action Threshold: If severe constipation, implement bowel regimen or consider dose adjustment.
Symptom Monitoring
- Dry mouth
- Blurred vision
- Dizziness
- Nausea
- Nervousness
- Constipation
- Urinary hesitancy or retention
- Confusion
- Disorientation
- Hallucinations
- Memory impairment
- Tachycardia
- Heat intolerance
Special Patient Groups
Pregnancy
Category C. Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks. Use only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Limited data, theoretical risk of developmental abnormalities.
Second Trimester:
Limited data.
Third Trimester:
Limited data, theoretical risk of anticholinergic effects in the neonate if used close to delivery.
Lactation
L3 (Moderately safe). Trihexyphenidyl is excreted into breast milk. Anticholinergic drugs can decrease milk production. Monitor infant for anticholinergic effects (e.g., drowsiness, constipation, urinary retention, dry mouth). Use with caution, especially in preterm or jaundiced infants.
Infant Risk:
Low to moderate risk. Potential for decreased milk supply and anticholinergic effects in the infant (e.g., sedation, constipation, urinary retention).
Pediatric Use
Safety and efficacy have not been established in children. Not generally recommended for pediatric use.
Geriatric Use
Elderly patients are particularly susceptible to the anticholinergic side effects of trihexyphenidyl, including confusion, hallucinations, memory impairment, urinary retention, and constipation. Start with lower doses and titrate slowly. Monitor closely for CNS and peripheral anticholinergic effects. Avoid use in elderly patients with cognitive impairment or dementia due to increased risk of delirium.
Clinical Information
Clinical Pearls
- Trihexyphenidyl is most effective for reducing tremor and rigidity in Parkinson's disease, but less effective for bradykinesia.
- It is also commonly used to manage drug-induced extrapyramidal symptoms (EPS) caused by antipsychotics, particularly dystonia and akathisia.
- Due to its anticholinergic properties, it should be used with caution in patients with prostatic hypertrophy, urinary retention, narrow-angle glaucoma, or cardiac arrhythmias.
- Patients should be advised to avoid sudden discontinuation of the drug, as this can lead to a worsening of Parkinsonian symptoms or withdrawal symptoms.
- Tolerance to some side effects (e.g., dry mouth, blurred vision) may develop over time, but cognitive side effects may persist or worsen.
- Consider alternative therapies in elderly patients or those with significant cognitive impairment due to the high risk of anticholinergic-induced delirium.
Alternative Therapies
- Other anticholinergic agents (e.g., benztropine, procyclidine) for Parkinsonism or drug-induced EPS.
- For Parkinson's disease: Levodopa/carbidopa, dopamine agonists (e.g., pramipexole, ropinirole), MAO-B inhibitors (e.g., selegiline, rasagiline), COMT inhibitors (e.g., entacapone), amantadine.
- For drug-induced EPS: Dose reduction of the offending antipsychotic, switching to an atypical antipsychotic with lower EPS risk, or other agents like beta-blockers (for akathisia) or benzodiazepines (for acute dystonia).
Cost & Coverage
Average Cost:
$10 - $50 per 30 tablets (5mg)
Generic Available:
Yes
Insurance Coverage:
Tier 1 or Tier 2 (preferred generic)
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 emergency medical attention. When seeking help, be prepared to provide details about the medication taken, the amount, and the time it happened.