Description
Pentoxifylline Pharmacodynamics
Pentoxifylline reduces blood viscosity and improves rheological properties of blood (fluidity) due to:
– improving the impaired deformability of erythrocytes;
– reduction of platelet and erythrocyte aggregation;
– decrease of fibrinogen concentration;
– decrease of leukocyte activity and decrease of leukocyte adhesion to vascular endothelium.
Pentoxifylline contains xanthine derivative – pentoxifylline as an active substance. Its mechanism of action is associated with phosphodiesterase inhibition and accumulation of cyclic adenosine monophosphate (cAMP) in vascular smooth muscle cells and blood cells. Having a weak myotropic vasodilator effect, pentoxifylline slightly reduces total peripheral vascular resistance and slightly dilates coronary vessels. Pentoxifylline has a weak positive inotropic effect on the heart. It improves microcirculation in the areas of impaired circulation.
Treatment with Pentoxifylline leads to improvement of symptoms of cerebral circulation disorders. In occlusive diseases of peripheral arteries the use of pentoxifylline leads to lengthening of walking distance, elimination of night cramps in the calf muscles and the disappearance of pain at rest.
Indications
– Peripheral arterial occlusive disease of atherosclerotic or diabetic genesis (e.g. intermittent claudication, diabetic angiopathy);
– trophic disorders (e.g., trophic ulcers of the lower leg, gangrene);
– cerebral circulatory disorders (consequences of cerebral atherosclerosis, e.g., reduced concentration, dizziness, memory impairment), ischemic and post-stroke conditions;
– circulatory disorders in the retina and vasculature of the eye;
– Otosclerosis, degenerative changes due to internal ear vascular pathology and hearing loss
Contraindications
– Hypersensitivity to pentoxifylline, other methylxanthines or to any of the ingredients
– massive hemorrhages, extensive retinal hemorrhages;
– acute myocardial infarction;
– cerebral hemorrhage;
– pronounced atherosclerosis of coronary arteries;
– pregnancy;
– Breast-feeding period;
– children under 18 years of age;
– lactose intolerance, lactase deficiency and glucose-galactose malabsorption syndrome.
Dosage and administration
- The dosage is set by the doctor in accordance with the individual characteristics of the patient. The drug should be swallowed in whole during or immediately after meals, with plenty of water.
- Normal dosage is: one tablet of Pentoxifylline three times a day with subsequent increase in dosage to 200 mg 2-3 times a day. Maximum single dose is 400 mg. The maximum daily dose is 1200 mg.
- In peripheral arterial occlusive disease stage II (intermittent claudication), the recommended dose of Pentoxifylline is 1200 mg daily (preferably as slow-release tablets 400 mg 3 times daily or 600 mg 2 times daily).
- In patients with impaired renal function (CKR less than 30 ml/min) the dose can be reduced to 1-2 tablets per day. Dosage reduction, taking into account individual tolerability, is necessary in patients with severe liver dysfunction.
- The treatment may be started in small doses in patients with low blood pressure as well as in patients at risk group due to possible blood pressure drop (patients with severe forms of CHD or with hemodynamically significant cerebral vascular stenosis). In these cases, the dose may be increased only gradually.