Pentoxifylline 400mg ER Tablets
It is used to ease pain, numbness, and tingling in the legs.It is used to treat certain blood vessel problems.It may be given to you for other reasons. Talk with the doctor.
Drug Class
Hemorheologic agent
Pharmacologic Class
Xanthine derivative
Pregnancy Category
Category C
FDA Approved
Aug 1984
DEA Schedule
Not Controlled
Overview
What is this medicine?
Pentoxifylline is a medication used to improve blood flow in people with a condition called intermittent claudication, which causes leg pain when walking due to poor circulation. It works by making your blood less thick and helping your red blood cells become more flexible, allowing them to pass more easily through narrow blood vessels.
How to Use This Medicine
Taking Your Medication Correctly
To get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. Take your medication with meals to help your body absorb it properly. Swallow the tablet whole - do not chew, break, or crush it. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store your medication at room temperature, away from light and moisture. Keep it in a dry place, such as a closet or drawer, and avoid storing it in the bathroom. Keep all medications out of the reach of children and pets to ensure their safety. If you have unused or expired medication, dispose of it properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. Check with your pharmacist for guidance on the best way to dispose of your medication, and consider participating in a drug take-back program in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember, with a meal. 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 get the most benefit from your medication, follow your doctor's instructions carefully. Read all the information provided with your prescription and follow the instructions closely. Take your medication with meals to help your body absorb it properly. Swallow the tablet whole - do not chew, break, or crush it. Continue taking your medication as directed by your doctor or healthcare provider, even if you start to feel better.
Storing and Disposing of Your Medication
Store your medication at room temperature, away from light and moisture. Keep it in a dry place, such as a closet or drawer, and avoid storing it in the bathroom. Keep all medications out of the reach of children and pets to ensure their safety. If you have unused or expired medication, dispose of it properly. Do not flush it down the toilet or pour it down the drain unless instructed to do so by your pharmacist. Check with your pharmacist for guidance on the best way to dispose of your medication, and consider participating in a drug take-back program in your area.
What to Do If You Miss a Dose
If you miss a dose, take it as soon as you remember, with a meal. 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 this medication with meals to reduce stomach upset.
- Swallow the extended-release tablets whole; do not crush, chew, or break them.
- It may take several weeks (e.g., 2-4 weeks) to notice an improvement in your symptoms. Continue taking the medication as prescribed.
- Smoking cessation is crucial for improving peripheral artery disease and maximizing the benefits of this medication.
- Regular exercise, as tolerated and recommended by your doctor, is also important for managing intermittent claudication.
Available Forms & Alternatives
Available Strengths:
Dosing & Administration
Adult Dosing
Standard Dose:
400 mg orally three times daily with meals
Dose Range:
400 - 1200 mg
Condition-Specific Dosing:
intermittentClaudication:
400 mg orally three times daily with meals. May reduce to 400 mg twice daily if adverse effects occur.
Pediatric Dosing
Neonatal:
Not established
Infant:
Not established
Child:
Not established
Adolescent:
Not established
Dose Adjustments
Renal Impairment:
Mild:
No specific adjustment needed for CrCl > 30 mL/min.
Moderate:
Consider dose reduction (e.g., 400 mg twice daily) if CrCl 10-30 mL/min.
Severe:
Reduce dose to 400 mg once or twice daily if CrCl < 30 mL/min.
Dialysis:
Administer after dialysis; significant reduction in dose (e.g., 400 mg once daily or every other day) may be necessary due to accumulation of active metabolites.
Hepatic Impairment:
Mild:
No specific adjustment needed.
Moderate:
Consider dose reduction (e.g., 400 mg twice daily).
Severe:
Significant dose reduction (e.g., 400 mg once daily) may be necessary due to impaired metabolism and increased plasma levels of parent drug and metabolites.
Confidence:
Medium
Pharmacology
Mechanism of Action
Pentoxifylline is a xanthine derivative that improves blood flow by decreasing blood viscosity and improving erythrocyte flexibility. It is thought to exert its hemorheologic effects by inhibiting phosphodiesterase, leading to increased intracellular cAMP in red blood cells, platelets, and vascular endothelium. This results in decreased blood viscosity, reduced platelet aggregation, and improved red blood cell deformability, thereby enhancing microcirculatory flow and tissue oxygenation in ischemic areas.
Pharmacokinetics
Absorption:
Bioavailability:
10-30%
Tmax:
2-4 hours (ER formulation)
FoodEffect:
Food delays absorption but does not significantly affect the extent of absorption. Taking with food may reduce gastrointestinal side effects.
Distribution:
Vd:
1.5 L/kg
ProteinBinding:
Approximately 45%
CnssPenetration:
Limited
Elimination:
HalfLife:
Parent drug: 0.5-1.5 hours; Metabolites: 1.5 hours
Clearance:
Not available
ExcretionRoute:
Primarily renal (95% as metabolites)
Unchanged:
<1%
Pharmacodynamics
OnsetOfAction:
Gradual, clinical improvement may take 2-4 weeks
PeakEffect:
Not precisely defined, sustained effect with ER formulation
DurationOfAction:
Sustained release provides effects over 8-12 hours per dose
Confidence:
Medium
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 notice 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
Chest pain or pressure
An irregular heartbeat
Severe dizziness or fainting
Unexplained bruising or bleeding
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although 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 persist, contact your doctor for advice:
Burping
Bloating
Gas
Upset stomach or vomiting
Dizziness or 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, 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.
While rare, some people may experience severe and potentially life-threatening side effects when taking this medication. If you notice 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
Chest pain or pressure
An irregular heartbeat
Severe dizziness or fainting
Unexplained bruising or bleeding
Other Possible Side Effects
Like all medications, this drug can cause side effects. Although 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 persist, contact your doctor for advice:
Burping
Bloating
Gas
Upset stomach or vomiting
Dizziness or 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, 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:
- Unusual bleeding or bruising
- Black, tarry stools or blood in urine
- Severe dizziness or fainting
- Chest pain or irregular heartbeat
- Severe nausea, vomiting, or stomach pain
- Allergic reaction (rash, itching, swelling, severe dizziness, trouble breathing)
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 recently had a bleeding problem in your brain or in the retina of your eye.
* If you are unable to consume products containing theophylline, theobromine, or caffeine.
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. They will help determine if it is safe to take this medication with your other medications and health conditions.
Remember, do not start, stop, or change the dose of any medication without first consulting your doctor to ensure your safety.
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 recently had a bleeding problem in your brain or in the retina of your eye.
* If you are unable to consume products containing theophylline, theobromine, or caffeine.
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. They will help determine if it is safe to take this medication with your other medications and health conditions.
Remember, do not start, stop, or change the dose of any medication without first consulting your doctor to ensure your safety.
Precautions & Cautions
It is essential to inform all your healthcare providers, including doctors, nurses, pharmacists, and dentists, that you are taking this medication. The full effects of this drug may not be apparent for several weeks. If you are 65 years or older, exercise caution when using this medication, as you may be more susceptible to side effects. Pregnant women, or those planning to become pregnant or who are breastfeeding, should consult their doctor to discuss the potential benefits and risks of this medication to both themselves and their baby.
Overdose Information
Overdose Symptoms:
- Flushing
- Hypotension (low blood pressure)
- Somnolence (drowsiness)
- Loss of consciousness
- Fever
- Agitation
- Seizures
- Nausea
- Vomiting
- Dizziness
- Tachycardia (fast heart rate)
What to Do:
Call 1-800-222-1222 (Poison Control Center) immediately or seek emergency medical attention. Treatment is generally supportive and symptomatic. Gastric lavage may be performed if ingestion is recent. Activated charcoal may be considered.
Drug Interactions
Major Interactions
Moderate Interactions
- Antihypertensive agents: Additive hypotensive effect, monitor blood pressure.
- Theophylline: Increased plasma levels of theophylline, leading to increased toxicity (nausea, vomiting, seizures).
- Cimetidine: May increase plasma concentrations of pentoxifylline and its metabolites, potentially increasing adverse effects.
Monitoring
Baseline Monitoring
Baseline symptoms of intermittent claudication (e.g., pain-free walking distance, maximal walking distance)
Rationale: To establish a baseline for assessing treatment efficacy.
Timing: Prior to initiation of therapy.
Blood pressure
Rationale: To monitor for potential hypotensive effects, especially in patients on antihypertensive medications.
Timing: Prior to initiation of therapy.
Routine Monitoring
Symptoms of intermittent claudication
Frequency: Periodically (e.g., every 2-4 weeks initially, then every 3-6 months)
Target: Improvement in pain-free and maximal walking distance
Action Threshold: Lack of improvement after 8 weeks may indicate need to discontinue or re-evaluate.
Blood pressure
Frequency: Periodically, especially during initial therapy or dose adjustments
Target: Maintain within patient's target range
Action Threshold: Significant hypotension or symptomatic orthostasis.
Signs of bleeding (e.g., bruising, petechiae, melena)
Frequency: Routinely, especially if co-administered with anticoagulants or antiplatelets
Target: Absence of abnormal bleeding
Action Threshold: Any signs of unusual bleeding.
Symptom Monitoring
- Dizziness
- Headache
- Nausea
- Vomiting
- Diarrhea
- Dyspepsia
- Abdominal discomfort
- Flushing
- Chest pain
- Arrhythmias
- Signs of bleeding (e.g., unusual bruising, nosebleeds, blood in stool/urine)
Special Patient Groups
Pregnancy
Pentoxifylline is classified as Pregnancy Category C. Animal studies have shown adverse effects on the fetus at doses higher than human therapeutic doses. There are no adequate and well-controlled studies in pregnant women. It should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Trimester-Specific Risks:
First Trimester:
Potential risk based on animal data; avoid if possible.
Second Trimester:
Potential risk based on animal data; use with caution.
Third Trimester:
Potential risk based on animal data; use with caution.
Lactation
Pentoxifylline and its metabolites are excreted in human breast milk. Due to the potential for serious adverse reactions in nursing 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. Lactation Risk Category L3 (Moderately Safe).
Infant Risk:
Potential for adverse effects (e.g., cardiovascular, gastrointestinal) in the infant. Monitor infant for signs of adverse effects.
Pediatric Use
Safety and effectiveness in pediatric patients have not been established. Not recommended for use in this population.
Geriatric Use
No specific dose adjustment is required based solely on age. However, elderly patients are more likely to have impaired renal or hepatic function, which may necessitate dose adjustments. Monitor for adverse effects and renal/hepatic function.
Clinical Information
Clinical Pearls
- Pentoxifylline is not a cure for peripheral artery disease (PAD) but can help manage symptoms of intermittent claudication.
- Full therapeutic effects may not be observed for 2-4 weeks, and some patients may require up to 8 weeks of therapy before significant improvement is noted.
- Patients should be advised to continue smoking cessation and exercise programs, as these are critical for managing PAD.
- Take with food to minimize gastrointestinal side effects.
- Do not crush or chew extended-release tablets.
- Monitor for signs of bleeding, especially in patients concurrently taking anticoagulants or antiplatelet agents.
Alternative Therapies
- Cilostazol (another phosphodiesterase inhibitor, often preferred for claudication)
- Supervised exercise therapy (first-line non-pharmacologic treatment)
- Antiplatelet agents (e.g., Aspirin, Clopidogrel - primarily for cardiovascular event risk reduction, not direct claudication symptom relief)
- Statins (for lipid management and cardiovascular risk reduction)
- Angioplasty or surgical revascularization (for severe cases)
Cost & Coverage
Average Cost:
Varies, typically $10-$50 per 30 tablets
Generic Available:
Yes
Insurance Coverage:
Tier 1 or 2 (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 occurred.