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Generic Name: pentoxifylline (PEN-tox-IF-i-lin)
Brand Name: Trental

Pentoxil is used for:

Treating intermittent claudication in certain patients to reduce pain, cramping, numbness, or weakness in the arms or legs. It may also be used for other conditions as determined by your doctor.

Pentoxil is a xanthine derivative. It works by making red blood cells more flexible, which helps to improve blood flow.

Do NOT use Pentoxil if:

  • you are allergic to any ingredient in Pentoxil or to methylxanthines (eg, theophylline, caffeine, theobromine)
  • you have had recent bleeding in the brain or eye

Contact your doctor or health care provider right away if any of these apply to you.

Before using Pentoxil:

Some medical conditions may interact with Pentoxil. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have stomach or bowel ulcers, blood vessel problems (eg, in the heart or brain), heart problems (eg, chest pain, irregular heartbeat), high or low blood pressure, liver problems, kidney problems, or a history of bleeding in the brain or eye
  • if you have recently had surgery
  • if you take medicine for high blood pressure

Some MEDICINES MAY INTERACT with Pentoxil. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Anticoagulants (eg, warfarin) or antiplatelet medicines (eg, clopidogrel) because the risk of bleeding may be increased
  • Ciprofloxacin or fluvoxamine because they may increase the risk of Pentoxil's side effects
  • Theophylline because the risk of its side effects may be increased by Pentoxil

This may not be a complete list of all interactions that may occur. Ask your health care provider if Pentoxil may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Pentoxil:

Use Pentoxil as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take Pentoxil by mouth with a meal.
  • Swallow Pentoxil whole. Do not break, crush, or chew before swallowing.
  • Continue to take Pentoxil even if you feel well. Do not miss any doses.
  • If you miss a dose of Pentoxil, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Pentoxil.

Important safety information:

  • Tell your doctor or dentist that you take Pentoxil before you receive any medical or dental care, emergency care, or surgery.
  • It may take 2 to 4 weeks to notice improvement in your condition, and up to 8 weeks for maximum relief. Do NOT take more than the recommended dose, change your dose, or take Pentoxil for longer than prescribed without checking with your doctor.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Pentoxil while you are pregnant. Pentoxil is found in breast milk. Do not breast-feed while taking Pentoxil.

Possible side effects of Pentoxil:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Belching; bloating; dizziness; flushing; gas; indigestion; nausea; stomach discomfort or upset; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blurred vision or other vision changes; chest pain; fainting; irregular heartbeat; severe or persistent dizziness or light-headedness; stomach pain; unusual bruising or bleeding; unusual tiredness or weakness; yellowing of the skin or eyes.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.

Proper storage of Pentoxil:

Store Pentoxil at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Pentoxil out of the reach of children and away from pets.

General information:

  • If you have any questions about Pentoxil, please talk with your doctor, pharmacist, or other health care provider.
  • Pentoxil is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take Pentoxil or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Pentoxil. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Pentoxil. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your health care provider for complete information about the risks and benefits of using Pentoxil.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer