Pentoxil

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

Pentoxifylline is an oral drug used for treating symptoms of intermittent claudication caused by peripheral arterial disease (PAD).

Tablets: 400 mg

Pentoxifylline should be stored at room temperature between 15 C - 30 C (59 F - 86 F), in a light resistant container.

Peripheral artery disease is caused by the build-up of cholesterol plaques in arteries of the legs. Plaque blocks arteries, reducing the flow of oxygen-carrying blood through the arteries to the muscles. This causes pain upon walking and reduces mobility. Peripheral artery disease is similar to coronary artery disease in which plaque builds up in heart arteries, causing chest pain (angina) because of a reduced supply of oxygen to the heart's muscle. Pentoxifylline, through unknown mechanisms, decreases the "stickiness" (viscosity) of blood and thereby improves its flow through arteries. This increases the flow of blood and oxygen to muscles and helps patients with intermittent claudication.

The FDA approved pentoxifylline in August 1984.

Pentoxil is part of the drug class:

• Purine derivatives

Serious side effects have been reported with Pentoxil. See the “Drug Precautions” section.

Common side effects include:

• upset stomach
• vomiting
• gas
• dizziness
• headache
• chest pain
• fast heartbeat

This is not a complete list of Pentoxil side effects. Ask your doctor or pharmacist for more information.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

In the U.S.

• Pentopak
• Pentoxil
• TRENtal

Available Dosage Forms:

• Tablet, Extended Release

Therapeutic Class: Hemorheologic

Chemical Class: Methylxanthine

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:

Allergies

Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.

Pediatric

Studies on this medicine have been done only in adult patients, and there is no specific information comparing use of pentoxifylline in children with use in other age groups.

Geriatric

Side effects may be more likely to occur in the elderly, who are usually more sensitive than younger adults to the effects of pentoxifylline.

Pregnancy

Breast Feeding

There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.

Interactions with Medicines

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.

Using this medicine with any of the following medicines is not recommended. Your doctor may decide not to treat you with this medication or change some of the other medicines you take.

• Ketorolac
• Riociguat

Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Aceclofenac
• Acemetacin
• Adenosine
• Amtolmetin Guacil
• Aspirin
• Bromfenac
• Bufexamac
• Celecoxib
• Choline Salicylate
• Clonixin
• Dexibuprofen
• Dexketoprofen
• Diclofenac
• Diflunisal
• Dipyrone
• Droxicam
• Etodolac
• Etofenamate
• Etoricoxib
• Felbinac
• Fenoprofen
• Fepradinol
• Feprazone
• Floctafenine
• Flufenamic Acid
• Flurbiprofen
• Ibuprofen
• Ibuprofen Lysine
• Indomethacin
• Ketoprofen
• Lornoxicam
• Loxoprofen
• Lumiracoxib
• Meclofenamate
• Mefenamic Acid
• Meloxicam
• Morniflumate
• Nabumetone
• Naproxen
• Nepafenac
• Niflumic Acid
• Nimesulide
• Nimesulide Beta Cyclodextrin
• Oxaprozin
• Oxyphenbutazone
• Parecoxib
• Phenylbutazone
• Piketoprofen
• Piroxicam
• Proglumetacin
• Propionic Acid
• Propyphenazone
• Proquazone
• Regadenoson
• Rofecoxib
• Salicylic Acid
• Salsalate
• Sodium Salicylate
• Sulindac
• Tenoxicam
• Tiaprofenic Acid
• Tolfenamic Acid
• Tolmetin
• Valdecoxib

Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.

• Acenocoumarol
• Cimetidine
• Dicumarol
• Theophylline
• Warfarin

Interactions with Food/Tobacco/Alcohol

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

• Any condition in which there is a risk of bleeding (e.g., recent stroke)—Pentoxifylline may make the condition worse

• Kidney disease or
• Liver disease—The chance of side effects may be increased

Pentoxil® (Pentoxifylline Extended-release Tablets, USP) for oral administration contain 400 mg of the active drug and the following inactive ingredients: D&C Red No. 27 Aluminum Lake, FD&C Blue No. 1 Aluminum Lake, hypromellose USP, magnesium stearate NF, polyethylene glycol NF, polysorbate 80 NF, povidone USP, silicon dioxide NF and titanium dioxide USP, in an extended-release formulation. Pentoxifylline is a tri-substituted xanthine derivative designated chemically as 3,7-Dihydro-3,7-dimethyl-1-(5-oxohexyl)-1H-purine-2,6-dione that, unlike theophylline, is a hemorrheologic agent, i.e., an agent that affects blood viscosity. Pentoxifylline is soluble in water and ethanol, and sparingly soluble in toluene. The structural formula is:

Meets USP Dissolution Test 3.

The usual dosage of Pentoxil® (Pentoxifylline Extended-release Tablets, USP) in extended-release tablet form is one tablet (400 mg) three times a day with meals.

While the effect of Pentoxil® (Pentoxifylline Extended-release Tablets, USP) may be seen within 2 to 4 weeks, it is recommended that treatment be continued for at least 8 weeks. Efficacy has been demonstrated in double-blind clinical studies of 6 months duration.

Digestive and central nervous system side effects are dose related. If patients develop these effects it is recommended that the dosage be lowered to one tablet twice a day (800 mg/day). If side effects persist at this lower dosage, the administration of Pentoxil® (Pentoxifylline Extended-release Tablets, USP) should be discontinued.

Applies to pentoxifylline: compounding powder, oral tablet extended release

General

Pentoxifylline (the active ingredient contained in Pentoxil) has been generally well tolerated. While typically minor, side effects have necessitated discontinuation of the drug in approximately 3% of treated patients. Tolerance to mild side effects generally has developed with continued use.[Ref]

Gastrointestinal

Gastrointestinal side effects have been the most common side effects associated with pentoxifylline (the active ingredient contained in Pentoxil) therapy and have included dyspepsia, nausea, vomiting, and belching, which occurred in 1% to 3% of patients. Some smaller studies have reported gastrointestinal disturbance in up to 33% of patients treated with pentoxifylline.[Ref]

Nervous system

Nervous system side effects have occurred in 1% to 2% of treated patients and have included headache, dizziness, insomnia, and tremor. Some smaller studies have reported nervous system adverse effects in up to 17% of treated patients. In addition, rare cases of visual and auditory hallucinations have been reported. Aseptic meningitis has been reported in postmarketing experiences.[Ref]

Cardiovascular

Cardiovascular side effects have included reports of palpitations, flushing, and angina. These reports have usually been associated with higher doses of an immediate release capsule which is not available in the United States.[Ref]

Hematologic

Hematologic side effects have included anecdotal reports of pancytopenia and fatal aplastic anemia.[Ref]

Hepatic

Hepatic side effects have included postmarketing reports of cholestasis.

Hypersensitivity

Hypersensitivity side effects have included postmarketing reports of anaphylactic reaction, anaphylactoid reaction, and anaphylactic shock.

Some side effects of Pentoxil may not be reported. Always consult your doctor or healthcare specialist for medical advice. You may also report side effects to the FDA.