Adverse reactions : תופעות לוואי

Adverse Reactions
Diarrhea and abdominal pain may occur with doses greater than 1 g/day.

Large doses {greater than 300 IU (135 mg potency)/day} have rarely caused intestinal cramps, fatigue, weakness, headache, blurred vision, rash, gonadal dysfunction, creatinuria, increased serum creatine kinase, increased serum cholesterol and triglycerides, increased urinary estrogens and androgens, and decreased serum thyroxine and triiodothyronine. These effects disappear after discontinuing the vitamin.

Precautions
Vitamin E has been reported to increase the risk of thrombosis in patients who are predisposed to this condition, including patients taking estrogens (see also Drug Interactions). This finding has not been confirmed but should be borne in mind when selecting patients for treatment, in particular women taking oral contraceptives containing oestrogen.

A higher incidence of necrotising enterocolitis has been noted in lower weight premature infants (less than 1.5kg) treated with vitamin E.

Drug Interactions
Vitamin E/Oral Anticoagulants: Vitamin E may interfere with vitamin K-dependent clotting factors. In patients on oral anticoagulant therapy who receive vitamin E concomitantly, the hypoprothrombinemic effects may be increased, possibly with bleeding. Therefore these patients should be observed closely for signs of an excessive hypoprothrombinemic response to oral anticoagulants, and coagulation indices monitored during concurrent administration of vitamin E. Lower anticoagulant doses may be required.

Evitol Tablets,               1 4. 2014, RH
Vitamin E/Estrogens: Vitamin E may increase the risk of thrombosis in patients taking estrogens.
Vitamin E/ Vitamin A: Vitamin A absorption, utilization and storage may be increased.
Vitamin E/Cholesterol Lowering Agents (e.g.: Colestipol, Cholestyramine, Gemfibrozil): These agents may decrease the absorption of vitamin E upon concomitant administration.
Vitamin E/Orlistat: Orlistat may decrease the absorption of fat-soluble vitamins, including vitamin E. It is therefore recommended that at least 2 hours elapse between doses of orlistat and vitamin E.

Dosage and Administration
Latest trends in vitamin E therapy favor high doses and prolonged treatment.

Adults
The usual dose is 200-400 mg daily. Larger doses up to 800 mg daily may be administered. In chronic diseases, treatment should be continued for at least 3 months.

Children
Up to half the adult dose.