Oxifyl CR400 mg

Oxifyl CR is a hemorheologic (blood flow-improving) agent with the following evidence-based uses:

Established / FDA-approved use

• Intermittent claudication due to chronic occlusive peripheral arterial disease (PAD) of the limbs — Oxifyl CR is indicated for the symptomatic treatment of intermittent claudication to improve walking distance and reduce leg pain/fatigue on exertion. It is used as an adjunct to standard PAD management (structured exercise, smoking cessation, and cardiovascular risk-factor control), not as a substitute for these measures or for revascularization when indicated.

Off-label / adjunct uses (variable evidence, not FDA-approved indications)

• Adjunct in chronic venous leg ulcers, in combination with compression therapy, to promote healing.
• Adjunct in diabetic nephropathy and diabetic microvascular complications, based on limited clinical trial data — physician judgment required.
• Adjunct in cerebrovascular insufficiency / vascular-type cognitive impairment in some regions, with modest and inconsistent evidence.

The decision to use Oxifyl CR for any off-label indication should be individualized by a qualified physician.

Each extended-release film-coated tablet contains Pentoxifylline USP 400 mg as the active ingredient, along with standard pharmaceutical excipients used for extended-release formulation. Pentoxifylline is chemically a dimethylxanthine derivative (a methylxanthine, structurally related to theophylline and caffeine).

Oxifyl CR is a hemorheologic agent belonging to the methylxanthine class of compounds. Unlike theophylline and caffeine, Oxifyl CR does not have significant central nervous system stimulant or bronchodilator activity; instead, its clinically relevant effect is on blood rheology (flow properties).

Oxifyl CR is used primarily to improve blood flow in patients with peripheral arterial disease who experience intermittent claudication (pain, cramping, or fatigue in the legs during walking that is relieved by rest).

Hemorheologic agent (peripheral blood flow modifier); methylxanthine derivative used in the management of intermittent claudication associated with Oxifyl CR-responsive peripheral arterial disease.

Mechanism

Pentoxifylline improves the flow properties of blood by reducing its viscosity. Proposed mechanisms include:

• Increasing red blood cell (erythrocyte) flexibility/deformability, allowing cells to pass more easily through narrowed or diseased microvasculature.
• Reducing blood viscosity by lowering plasma fibrinogen concentration and enhancing fibrinolytic activity.
• Inhibiting platelet aggregation and reducing the tendency of red cells and platelets to clump together.
• Non-selective phosphodiesterase inhibition, raising intracellular cyclic AMP in blood cells and vascular tissue.

Pharmacokinetics

Pentoxifylline is well absorbed after oral administration, undergoes extensive first-pass hepatic metabolism to several active metabolites, and is eliminated mainly renally. It has a short plasma half-life, which is why extended-release formulations are used to maintain therapeutic effect with less frequent dosing.

Oxifyl CR extended-release tablets should be taken with or immediately after meals to reduce the chance of gastrointestinal upset. Swallow the tablet whole with a full glass of water; do not crush, chew, or split it, as this destroys the extended-release mechanism and may cause too much drug to be released at once.

• Anticoagulants and antiplatelet agents (e.g., warfarin, aspirin, clopidogrel): Oxifyl CR can further inhibit platelet aggregation; concurrent use increases the risk of bleeding. Monitor closely for signs of bleeding and adjust therapy as needed.
• Theophylline and other xanthine derivatives: Oxifyl CR may raise plasma theophylline concentrations, increasing the risk of theophylline toxicity (nausea, tremor, seizures).
• Antihypertensive agents: Oxifyl CR has mild blood-pressure–lowering activity; concurrent use with antihypertensives may result in additive hypotension, requiring dose adjustment of the antihypertensive.
• Cimetidine: may increase plasma levels of Oxifyl CR and its metabolites; monitor for increased side effects.

Common

• Nausea, dyspepsia, vomiting, abdominal discomfort (often improved by taking Oxifyl CR with food)
• Dizziness, headache
• Flushing

Less common / serious (seek medical attention)

• Bleeding (see Contraindications/Precautions for anticoagulant interaction)
• Chest pain, palpitations, or cardiac arrhythmia
• Allergic reactions including rash, itching, or angioedema (swelling of face/throat)
• Rare blood dyscrasias (e.g., aplastic anemia, thrombocytopenia, leukopenia) and rare hepatic reactions (jaundice, elevated liver enzymes)

Pregnancy: Oxifyl CR should be used during pregnancy only if clearly needed and if the potential benefit justifies the potential risk to the fetus. Adequate, well-controlled human studies are lacking; a physician should be consulted before use in pregnancy.

Lactation: Oxifyl CR and its metabolites are excreted into human breast milk in small amounts. Caution is advised when Oxifyl CR is administered to a breastfeeding woman, and a physician should be consulted to weigh benefits against potential risk to the infant.

• Bleeding risk: Use Oxifyl CR with caution in patients on anticoagulant or antiplatelet therapy and in those with a bleeding tendency; monitor for signs of bleeding (see Interactions).
• Cardiac disease: Use with caution in patients with coronary artery disease (e.g., recent myocardial infarction, unstable angina) or arrhythmias, as clinical judgment is required given the drug's cardiovascular effects.
• Renal or hepatic impairment: Dose adjustment may be needed; use with caution and closer monitoring (see Use in Special Populations).
• Not a substitute for standard PAD care: Oxifyl CR provides modest symptomatic benefit and should be used as an adjunct to exercise therapy, smoking cessation, and cardiovascular risk-factor management — not as sole or primary therapy for peripheral arterial disease.
• CNS effects: Dizziness may occur; use caution when driving or operating machinery until the individual response to Oxifyl CR is known.

Reported symptoms of Oxifyl CR overdose include flushing, hypotension, seizures, drowsiness, agitation, fever, and loss of consciousness; symptoms may be delayed for several hours. There is no specific antidote.

If overdose is suspected, seek immediate medical attention or contact emergency services/poison control right away. Treatment is supportive and symptomatic, and must be provided by qualified medical personnel; do not attempt specific home treatment.

Store at room temperature (below 30°C), away from light and moisture. Keep out of reach of children.

• Renal impairment: Oxifyl CR and its metabolites are largely renally excreted; patients with significant renal impairment should be started at a reduced dose and monitored closely for increased side effects.
• Hepatic impairment: Since Oxifyl CR undergoes extensive hepatic metabolism, patients with hepatic impairment may need a reduced dose and closer monitoring.
• Elderly: No specific dose adjustment is established, but elderly patients may be more sensitive to dizziness and gastrointestinal side effects; monitor accordingly.
• Pediatric patients: Safety and efficacy have not been established; Oxifyl CR is not recommended for use in children (see Pediatric Uses).

A therapeutic trial of Oxifyl CR for at least 8 weeks is generally needed to assess symptomatic benefit in intermittent claudication. If no improvement in walking distance or symptoms is seen after 8 weeks, the physician should reassess continued use. If benefit is seen, Oxifyl CR may be continued long-term under periodic physician review, alongside ongoing exercise and risk-factor management.

Hemorheologic agents; methylxanthine derivatives. Pentoxifylline is the representative agent of this class used for peripheral arterial disease.

Pentoxifylline lowers blood viscosity and improves microcirculatory flow by increasing red blood cell flexibility, reducing plasma fibrinogen, enhancing fibrinolysis, and inhibiting platelet aggregation, via non-selective phosphodiesterase inhibition. The net effect is improved delivery of oxygen to poorly perfused tissues, such as the calf muscles in patients with peripheral arterial disease.

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Safety and efficacy of Oxifyl CR have not been established in pediatric patients. Oxifyl CR is therefore not recommended for use in children and adolescents outside of specialist supervision.