Two softgels contain: Vitamin A (retinyl palmitate) 300 IU • Vitamin E (alpha-tocomonoenol) 1 IU • Antarctic Krill Oil providing: Omega 3 Fatty Acids 130 mg, Eicosapentaenoic Acid (EPA) 50 mg, Docosahexaenoic Acid (DHA) 20 mg, Omega-6 fatty acids 20 mg, Astaxanthin 1.5 mg. Other Ingredients: Gelatin, Bovine Source (capsule).
Brand name products often contain multiple ingredients. To read detailed information about each ingredient, click on the link for the individual ingredient shown above.
Below is general information about the effectiveness of the known ingredients contained in the product Krill Oil 500 mg. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product Krill Oil 500 mg. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
POSSIBLY SAFE ...when used orally and appropriately, short-term. Krill oil has been used safely at doses of up to 4 grams daily in clinical trials lasting for up to 6 months (15753,15754,15760,19374,91600,96114,96162,107474,110370).
CHILDREN: POSSIBLY SAFE
when used orally and appropriately (110372,110374).
In children 14 years of age, krill oil 4 grams daily, providing doses of eicosapentaenoic acid (EPA) 520 mg and docosahexaenoic acid (DHA) 280 mg daily, has been used with apparent safety for up to 12 months (110372,110374).
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally or intramuscularly and appropriately. Vitamin A, as pre-formed vitamin A (retinol or retinyl ester), is safe in adults when taken in doses below the tolerable upper intake level (UL) of 10,000 IU (3000 mcg) per day (7135). Higher doses increase the risk of side effects. There is also growing concern that taking high doses of antioxidants such as vitamin A might do more harm than good. In an analysis of studies, taking vitamin A supplements alone or in combination with other antioxidants is associated with an increased risk of mortality from all causes (15305,90775). Keep in mind that vitamin A is available in two different forms: pre-formed vitamin A (retinol or retinyl ester) and provitamin A (carotenoids). The safety concerns associated with high vitamin A intake occur with pre-formed vitamin A only. Some supplements contain vitamin A in both pre-formed and provitamin A forms. For these supplements, the amount of pre-formed vitamin A should be used to determine if the amount of vitamin A is safe.
POSSIBLY SAFE ...when used topically and appropriately, short-term. Retinol 0.5% has been used on the skin daily for up to 12 weeks with apparent safety. No serious adverse effects have been reported in clinical trials (103671,103680).
POSSIBLY UNSAFE ...when used orally in high doses. Doses higher than the UL of 10,000 IU (3000 mcg) per day of pre-formed vitamin A (retinol or retinyl ester) might increase the risk of side effects (7135). While vitamin A 25,000 IU (as retinyl palmitate) daily for 6 months followed by 10,000 IU daily for 6 months has been used with apparent safety in one clinical trial (95052), prolonged use of excessive doses of vitamin A can cause significant side effects such as hypervitaminosis A. The risk for developing hypervitaminosis A is related to total cumulative dose of vitamin A rather than a specific daily dose (1467,1469). There is also concern that taking high doses of antioxidants such as vitamin A might do more harm than good. In an analysis of studies, taking vitamin A supplements alone or in combination with other antioxidants is associated with an increased risk of mortality from all causes (15305,90775). There is insufficient reliable information available about the safety of using sublingual formulations of vitamin A.
CHILDREN: LIKELY SAFE
when used orally or intramuscularly and appropriately.
The amount of pre-formed vitamin A (retinol or retinyl ester) that is safe depends on age. For children up to 3 years of age, doses less than 2000 IU (600 mcg) per day seem to be safe. For children ages 4 to 8, doses less than 3000 IU (900 mcg) per day seem to be safe. For children ages 9 to 13, doses less than 5667 IU (1700 mcg) per day seem to be safe. For children 14 to 18, doses less than 9333 IU (2800 mcg) per day seem to be safe (7135). Keep in mind that vitamin A is available in two different forms: pre-formed vitamin A (retinol or retinyl ester) and provitamin A (carotenoids). The safety concerns associated with high vitamin A intake occur with pre-formed vitamin A only. Some supplements contain vitamin A in both pre-formed and provitamin A forms. For these supplements, the amount of pre-formed vitamin A should be used to determine if the amount of vitamin A is safe.
CHILDREN: POSSIBLY UNSAFE
when pre-formed vitamin A (retinol or retinyl ester) is used orally in excessive doses.
For children up to 3 years of age, avoid doses greater than 2000 IU (600 mcg) per day. For children ages 4 to 8, avoid doses greater than 3000 IU (900 mcg) per day. For children ages 9 to 13, avoid doses greater than 5667 IU (1700 mcg) per day. For children ages 14 to 18, avoid doses greater than 9333 IU (2800 mcg) per day (7135). Higher doses of vitamin A supplementation have been associated with increased risk of side effects such as pneumonia, bone pain, and diarrhea (319,95051). Long-term supplementation with low to moderate doses on a regular basis can cause severe, but usually reversible, liver damage (11978).
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally or intramuscularly and appropriately.
Vitamin A, as pre-formed vitamin A (retinol or retinyl ester), is safe during pregnancy and lactation when used in doses less than 10,000 IU (3000 mcg) per day (7135,16823,107293). Keep in mind that vitamin A is available in two different forms: pre-formed vitamin A (retinol or retinyl ester) and provitamin A (carotenoids). The safety concerns associated with high vitamin A intake occur with pre-formed vitamin A only. Some supplements contain vitamin A in both pre-formed and provitamin A forms. For these supplements, the amount of pre-formed vitamin A should be used to determine if the amount of vitamin A is safe.
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally or intramuscularly in excessive doses.
Daily intake of greater than 10,000 IU (3000 mcg) can cause fetal malformations (3066,7135). Excessive dietary intake of vitamin A has also been associated with teratogenicity (11978). The first trimester of pregnancy seems to be the critical period for susceptibility to vitamin A-associated birth defects such as craniofacial abnormalities and abnormalities of the central nervous system (7135). Pregnant patients should monitor their intake of pre-formed vitamin A (retinol or retinyl ester). This form of vitamin A is found in several foods including animal products, some fortified breakfast cereals, and dietary supplements (3066).
LIKELY SAFE ...when used orally or topically and appropriately. Vitamin E is generally considered safe, even at doses exceeding the recommended dietary allowance (RDA); however, adverse effects are more likely to occur with higher doses. The tolerable upper intake level (UL) in healthy people is 1000 mg daily, equivalent to 1100 IU of synthetic vitamin E (all-rac-alpha-tocopherol) or 1500 IU of natural vitamin E (RRR-alpha-tocopherol) (4668,4681,4713,4714,4844,89234,90067,90069,90072,19206)(63244,97075). Although there is some concern that taking vitamin E in doses of 400 IU (form unspecified) per day or higher might increase the risk of adverse outcomes and mortality from all causes (12212,13036,15305,16709,83339), most of this evidence comes from studies that included middle-aged or older patients with chronic diseases or patients from developing countries in which nutritional deficiencies are prevalent.
POSSIBLY UNSAFE ...when used orally in high doses. Repeated doses exceeding the tolerable upper intake level (UL) of 1000 mg daily are associated with significant side effects in otherwise healthy people (4844). ...when used intravenously in large doses. Large repeated intravenous doses of all-rac-alpha-tocopherol (synthetic vitamin E) were associated with decreased activity of clotting factors and bleeding in one report (3074). ...when inhaled. E-cigarette, or vaping, product-use associated lung injury (EVALI) has occurred among adults who use e-cigarette, or vaping, products, which often contain vitamin E acetate. In some cases, this has resulted in death. The majority of patients with EVALI reported using tetrahydrocannabinol (THC)-containing products in the 3 months prior to the development of symptoms. Vitamin E acetate has been detected in most bronchoalveolar lavage samples taken from patients with EVALI. Other ingredients, including THC or nicotine, were also commonly found in samples. However, priority toxicants including medium chain triglyceride (MCT) oil, plant oil, petroleum distillate, or terpenes, were undetectable in almost all samples. While this association shows a correlation between vitamin E acetate inhalation and lung injury, a causal link has not yet been determined, and it is not clear if other toxic compounds are also involved (101061,101062,102970).
CHILDREN: LIKELY SAFE
when used orally and appropriately.
Vitamin E has been safely used in children in amounts below the tolerable upper intake level (UL). The UL for healthy children is: 200 mg in children aged 1-3 years, 300 mg in children aged 4-8 years, 600 mg in children aged 9-13 years, and 800 mg in children aged 14-18 years. A UL has not been established for infants up to 12 months of age (23388).
CHILDREN: POSSIBLY UNSAFE
when used orally in doses above the UL due to increased risk of adverse effects (23388).
...when alpha-tocopherol is used intravenously in large doses in premature infants. Large intravenous doses of vitamin E are associated with an increased risk of necrotizing enterocolitis and sepsis in this population (85062,85083). ...when inhaled. E-cigarette, or vaping, product-use associated lung injury (EVALI) has occurred among adolescents and teenagers who use e-cigarette, or vaping, products. In some cases, this has resulted in death. The majority of patients with EVALI reported using tetrahydrocannabinol (THC)-containing products in the 3 months prior to the development of symptoms. Constituents in E-cigarette or vaping products with the potential to cause lung injury or impaired lung function include lipids, such as vitamin E acetate. Vitamin E acetate has been detected in all bronchoalveolar lavage samples taken from patients with EVALI. No other ingredient, including THC or nicotine, was found in all samples, and other ingredients, including medium chain triglyceride (MCT) oil, plant oil, petroleum distillate, or terpenes, were undetectable This shows that vitamin E acetate is at the primary site of lung injury. A causal link has not yet been described and it is not clear if other compounds are also involved (101061,101062).
PREGNANCY: POSSIBLY SAFE
when used orally and appropriately.
The tolerable upper intake level (UL) during pregnancy is 800 mg for those 14-18 years of age and 1000 mg for those 19 years and older. However, maternal supplementation is not generally recommended unless dietary vitamin E falls below the RDA (4260). No serious adverse effects were reported with oral intake of 400 IU per day starting at weeks 9-22 of pregnancy in healthy patients or those at high risk for pre-eclampsia (3236,97075), or with 600-900 IU daily during the last two months of pregnancy (4260). However, some preliminary evidence suggests that taking vitamin E supplements might be harmful when taken in early pregnancy. A case-control study found that taking a vitamin E supplement during the first 8 weeks of pregnancy is associated with a 1.7-9-fold increase in odds of congenital heart defects (16823). However, the exact amount of vitamin E consumed during pregnancy in this study is unclear. Until more is known, advise patients to avoid taking a vitamin E supplement in early pregnancy unless needed for an appropriate medical indication.
LACTATION: LIKELY SAFE
when used orally in amounts that do not exceed the tolerable upper intake level (UL).
The UL during lactation is 800 mg for those 14-18 years of age and 1000 mg for those 19 years and older (4844).
LACTATION: POSSIBLY UNSAFE
when used orally in amounts that exceed the UL due to increased risk of adverse effects (4844).
Below is general information about the interactions of the known ingredients contained in the product Krill Oil 500 mg. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
Theoretically, krill oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
 Details
Taking high doses of omega-3 fatty acids from fish oil can modestly decrease platelet aggregation (8671,8679,8696,19375). Since krill oil also contains these fatty acids, taking high doses of krill oil might also inhibit platelet aggregation. Theoretically, taking high doses of krill oil with antiplatelet or anticoagulant drugs might increase the risk of bleeding. However, the omega-3 content of krill oil is much lower than that of fish oil.
|
Theoretically, taking krill oil with antidiabetes drugs might increase the risk of hypoglycemia.
Details
|
Theoretically, taking high doses of vitamin A in combination with other potentially hepatotoxic drugs might increase the risk of liver disease.
Details
|
Concomitant use of retinoids with vitamin A supplements might produce supratherapeutic vitamin A levels.
Details
Retinoids, which are vitamin A derivatives, could have additive toxic effects when taken with vitamin A supplements (3046).
|
Theoretically, taking tetracycline antibiotics with high doses of vitamin A can increase the risk of pseudotumor cerebri.
Details
Benign intracranial hypertension (pseudotumor cerebri) can occur with tetracyclines and with acute or chronic vitamin A toxicity. Case reports suggest that taking tetracyclines and vitamin A concurrently can increase the risk of this condition (10545,10546,10547). Avoid high doses of vitamin A in people taking tetracyclines chronically.
|
Theoretically, high doses of vitamin A could increase the risk of bleeding with warfarin.
Details
Vitamin A toxicity is associated with hemorrhage and hypoprothrombinemia, possibly due to vitamin K antagonism (505). Advise patients taking warfarin to avoid doses of vitamin A above the tolerable upper intake level of 10,000 IU/day for adults.
|
Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of alkylating agents.
Details
There's concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa (391). However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells (14012,14013). More evidence is needed to determine what effect, if any, antioxidants such as vitamin E have on chemotherapy. Advise patients to consult their oncologist before using vitamin E supplements, especially in high doses.
|
Concomitant use of vitamin E and anticoagulant or antiplatelet agents might increase the risk of bleeding.
Details
Vitamin E seems to inhibit of platelet aggregation and antagonize the effects of vitamin K-dependent clotting factors (4733,4844,11580,11582,11583,11584,11586,112162). These effects appear to be dose-dependent, and are probably only likely to be clinically significant with doses of at least 800 units daily (11582,11585). Mixed tocopherols, such as those found in food, might have a greater antiplatelet effect than alpha-tocopherol (10364). RRR alpha-tocopherol (natural vitamin E) 1000 IU daily antagonizes vitamin K-dependent clotting factors (11999). Advise patients to avoid high doses of vitamin E, especially in people with low vitamin K intake or other risk factors for bleeding.
|
Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of antitumor antibiotics.
Details
There's concern that antioxidants could reduce the activity of antitumor antibiotic drugs such as doxorubicin, which generate free radicals (391). However, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that might interfere with apoptosis (cell death) of cancer cells (14012,14013). More evidence is needed to determine what effect, if any, antioxidants such as vitamin E have on chemotherapy involving antitumor antibiotics. Advise patients to consult their oncologist before using vitamin E supplements, especially in high doses.
|
A specific form of vitamin E might increase absorption and levels of cyclosporine.
Details
There is some evidence that one specific formulation of vitamin E (D-alpha-tocopheryl-polyethylene glycol-1000 succinate, TPGS, tocophersolan, Liqui-E) might increase absorption of cyclosporine. This vitamin E formulation forms micelles which seems to increase absorption of cyclosporine by 40% to 72% in some patients (624,625,10368). However, this interaction is unlikely to occur with the usual forms of vitamin E.
|
Theoretically, vitamin E might induce metabolism of CYP3A4, possibly reducing the levels CYP3A4 substrates.
Details
Vitamin E appears to bind with the nuclear receptor, pregnane X receptor (PXR), which results in increased expression of CYP3A4 (13499,13500). Although the clinical significance of this is not known, use caution when considering concomitant use of vitamin E and other drugs affected by these enzymes.
|
Vitamin E might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
Details
A combination of niacin and simvastatin (Zocor) effectively raises high-density lipoprotein (HDL) cholesterol levels in people with coronary disease and low HDL levels. Clinical research shows that taking a combination of antioxidants (vitamin C, vitamin E, beta-carotene, and selenium) along with niacin and simvastatin (Zocor) attenuates this rise in HDL, specifically the HDL-2 and apolipoprotein A1 fractions, by more than 50% (7388,11537). Vitamin E alone combined with a statin does not seem to decrease HDL levels (11286,11287). It is not known whether the adverse effect on HDL is due to one of the other antioxidants or to the combination. It also is not known whether it will occur in other patient populations.
|
Taking selumetinib with vitamin E can result in a total daily dose of vitamin E that exceeds safe limits and therefore might increase the risk of bleeding.
Details
Selumetinib contains 48-54 IU vitamin E per capsule (102971). The increased risk of bleeding with vitamin E appears to be dose-dependent (11582,11585,34577). Be cautious when using selumetinib in combination with supplemental vitamin E, especially in patients at higher risk of bleed, such as those with chronic conditions and those taking antiplatelet drugs (102971).
|
Using vitamin E with warfarin might increase the risk of bleeding.
Details
Due to interference with production of vitamin K-dependent clotting factors, use of more than 400 IU of vitamin E daily with warfarin might increase prothrombin time (PT), INR, and the risk of bleeding, (91,92,93). At a dose of 1000 IU per day, vitamin E can antagonize vitamin K-dependent clotting factors even in people not taking warfarin (11999). Limited clinical evidence suggests that doses up to 1200 IU daily may be used safely by patients taking warfarin, but this may not be applicable in all patient populations (90).
|
Below is general information about the adverse effects of the known ingredients contained in the product Krill Oil 500 mg. Some ingredients may not be listed. This information does NOT represent a recommendation for or a test of this specific product as a whole.
General
...Orally, krill oil seems to be well tolerated when used in doses up to 4 grams daily.
Most Common Adverse Effects:
Orally: Bloating, decreased appetite, diarrhea, fishy burps, flatulence, heartburn, nausea, and stomach discomfort.
Cardiovascular ...Orally, krill oil may cause hypertension, but this effect has only been observed for one patient in one clinical trial (91600).
Dermatologic ...Orally, krill oil may cause minor facial skin rash, skin oiliness, or localized pimples (15754,91599,110372,110374).
Gastrointestinal ...Orally, krill oil may cause gastrointestinal side effects including stomach discomfort or upset, decreased appetite, taste change, heartburn, fishy burps, bloating, flatulence, diarrhea, vomiting, and nausea (57836,91599,91600,110372,110374). However, these effects seem to be less severe or occur less often with krill oil compared to fish oil (15754).
Neurologic/CNS ...When taken orally, headache, tiredness, and dizziness have been reported rarely in clinical research (110372,110374).
Pulmonary/Respiratory ...When taken orally, sore throat has been reported rarely in clinical research (110372,110374).
General
...Orally, vitamin A is generally well-tolerated at doses below the tolerable upper intake level (UL).
Serious Adverse Effects (Rare):
Orally: In very high doses, vitamin A can cause pseudotumor cerebri, pain, liver toxicity, coma, and even death.
Dermatologic ...Chronic oral use of large amounts of vitamin A causes symptoms of vitamin A toxicity including dry skin and lips; cracking, scaling, and itchy skin; skin redness and rash; hyperpigmentation; shiny skin, and massive skin peeling (7135,95051). Hypervitaminosis A can cause brittle nails, cheilitis, gingivitis, and hair loss (15,95051). Adverse effects from a single ingestion of a large dose of vitamin A is more common in young children than adults (15). In children, approximately 25,000 IU/kg can cause skin redness and generalized peeling of the skin a few days later and may last for several weeks (15).
Gastrointestinal ...There is some evidence that oral vitamin A supplementation might increase the risk of diarrhea in children. Although vitamin A can prevent diarrhea and reduce mortality in malnourished children, doses as low as 10,000 IU weekly for 40 weeks have been associated with diarrhea in well-nourished children (319). Diarrhea (82326,82389), nausea (7135,100329), abdominal pain (95051), abdominal fullness (100329), and vomiting (7135,82559,95051,95055,109755) have been reported following use of large doses of oral vitamin A. Adverse effects from a single ingestion of a large dose of vitamin A is more common in young children than adults (15). In children, approximately 25,000 IU/kg can cause vomiting and diarrhea (15). Chronic use of large amounts of vitamin A causes symptoms of vitamin A toxicity including anorexia, abdominal discomfort, and nausea and vomiting (7135).
Genitourinary ...Hypervitaminosis A can cause reduced menstrual flow (15). Intravaginally, all-trans retinoic acid can cause vaginal discharge, itching, irritation, and burning (9199).
Hematologic ...Hypervitaminosis A can cause spider angiomas, anemia, leukopenia, leukocytosis, and thrombocytopenia (15,95051).
Hepatic ...Since the liver is the main storage site for vitamin A, hypervitaminosis A can cause hepatotoxicity, with elevated liver enzymes such as alanine aminotransferase (ALT, formerly SGPT) and aspartate aminotransferase (AST, formerly SGOT), as well as fibrosis, cirrhosis, hepatomegaly, portal hypertension, and death (6377,7135,95051).
Musculoskeletal
...Vitamin A can increase the risk for osteoporosis and fractures.
Observational research has found that chronic, high intake of vitamin A 10,000 IU or more per day is associated with an increased risk of osteoporosis and hip fracture in postmenopausal adults, as well as overall risk of fracture in middle-aged males (7712,7713,9190). A meta-analysis of these and other large observational studies shows that high dietary intake of vitamin A or retinol is associated with a 23% to 29% greater risk of hip fracture when compared with low dietary intake (107294). High serum levels of vitamin A as retinol also increase the risk of fracture in males. Males with high serum retinol levels are seven times more likely to fracture a hip than those with lower serum retinol levels (9190). Vitamin A damage to bone can occur subclinically, without signs or symptoms of hypervitaminosis A. Some researchers are concerned that consumption of vitamin A fortified foods such as margarine and low-fat dairy products in addition to vitamin A or multivitamin supplements might cause excessive serum retinol levels. Older people have higher levels of vitamin A and might be at increased risk for vitamin A-induced osteoporosis.
Vitamin A's effects on bone resorption could lead to hypercalcemia (95051).
Hypervitaminosis can cause slow growth, premature epiphyseal closure, painful hyperostosis of the long bones, general joint pain, osteosclerosis, muscle pain, and calcium loss from the bones (15,95051). One child experienced severe bone pain after taking vitamin A 600,000 IU daily for more than 3 months (95051). Vitamin A was discontinued and symptoms lessened over a period of 2 weeks. The patient made a full recovery 2 months later.
Neurologic/CNS
...Orally, adverse effects from a single large dose of vitamin A are more common in young children than adults (15).
Headache, increased cerebrospinal fluid pressure, vertigo, and blurred vision have been reported following an acute oral dose of vitamin A 500,000 IU (7135). In children, approximately 25,000 IU/kg can cause headache, irritability, drowsiness, dizziness, delirium, and coma (15). Chronic use of large amounts of vitamin A causes symptoms of vitamin A toxicity including fatigue, malaise, lethargy, and irritability (7135).
There are reports of bulging of the anterior fontanelle associated with an acute high oral dose of vitamin A in infants (7135,90784,95053,95054). In children, approximately 25,000 IU/kg can cause increased intracranial pressure with bulging fontanelles in infants (15). Also, muscular incoordination has been reported following short-term high doses of vitamin A (7135).
A case of intracranial hypertension involving diffuse headaches and brief loss of vision has been reported secondary to topical use of vitamin A. The patient was using over-the-counter vitamin A preparations twice daily including Avotin 0.05% cream, Retin-A gel 0.01%, and Isotrexin gel containing isotretinoin 0.05% and erythromycin 2%, for treatment of facial acne. Upon exam, the patient was noted to have bilateral optic disc edema. The patient discontinued use of topical vitamin A products. Two months later, the patient reported decreased headaches and an improvement in bilateral optic disc edema was seen (95056).
Ocular/Otic ...In children, oral vitamin A approximately 25,000 IU/kg can cause swelling of the optic disk, bulging eyeballs, and visual disturbances (15). Adverse effects from a single ingestion of a large dose of vitamin A are more common in young children than adults (15).
Oncologic ...There is concern that high intake of vitamin A might increase some forms of cancer. Population research suggests high vitamin A intake might increase the risk of gastric carcinoma (9194).
Psychiatric ...Chronic oral use of large amounts of vitamin A causes symptoms of vitamin A toxicity, which can include symptoms that mimic severe depression or schizophrenic disorder (7135).
Pulmonary/Respiratory ...There is some evidence that oral vitamin A supplementation might increase the risk of pneumonia and diarrhea in children. Although vitamin A can prevent diarrhea and reduce mortality in malnourished children, doses as low as 10,000 IU weekly for 40 weeks have been associated with pneumonia and diarrhea in well-nourished children (319). In preschool children, high-dose vitamin A also increases the risk of respiratory infection (82288).
Other ...Chronic use of large amounts of vitamin A (>25,000 IU daily for more than 6 years or 100,000 IU daily for more than 6 months) can cause symptoms of vitamin A toxicity including mild fever and excessive sweating (7135). High intakes of vitamin A may result in a failure to gain weight normally in children and weight loss in adults (15).
General
...Orally and topically, vitamin E is generally well-tolerated.
Serious Adverse Effects (Rare):
Orally: Bleeding, hemorrhagic stroke, cardiovascular complications.
Inhaled: Vitamin E acetate is thought to be responsible for e-cigarette, or vaping, product-use associated lung injury (EVALI).
Cardiovascular
...Some evidence suggests that taking vitamin E supplements, especially greater than or equal to 400 IU taken by mouth daily for over one year, might also increase the risk of mortality in non-healthy patients (12212,13036,15305,16709,83339).
A population study shows that vitamin E use is associated with a significantly increased risk of mortality in people with a history of severe cardiovascular disease such as stroke or myocardial infarction (16709). In an analysis of clinical trials, patients who took either all-rac-alpha-tocopherol (synthetic vitamin E) or RRR-alpha-tocopherol (natural vitamin E) in doses of 400 IU/day or higher had an increased risk of mortality from all causes. The risk of mortality seems to increase when higher doses are used (12212). A large-scale study also suggests that patients with diabetes or cardiovascular disease who take RRR-alpha-tocopherol (natural vitamin E) 400 IU daily have an increased risk of heart failure and heart failure-related hospitalization (13036). However, in another large scale study, taking 600 IU vitamin E every other day for 10 years did not increase the risk of heart failure in healthy females over 45 years of age (90068). There is speculation that high-dose vitamin E might disrupt the normal antioxidant balance and result in pro-oxidant rather than antioxidant effects.
There is some evidence that vitamin E in combination with simvastatin (Zocor), niacin, selenium, vitamin C, and beta-carotene might lower high density lipoprotein-2 (HDL-2) by 15%. HDL-2 is considered to be the most cardioprotective component of HDL (7388). However, vitamin E and a statin alone don't seem to negatively affect HDL (11286,11287). In addition, vitamin E has been associated with increased triglycerides (85215). Although only certain isomers of vitamin E are included for determination of dietary requirements, all isomers are considered for determining safe intake levels. All the isomers are thought to potentially contribute to toxicity.
Dermatologic
...Topically, vitamin E has been associated with contact dermatitis, inflammatory reactions, and eczematous lesions (11998,85066,85285).
Dermatitis, often associated with moisturizers containing vitamin E, has a scattered generalized distribution, is more common on the face than the hands, and is more common in females with a history of atopic dermatitis. In a retrospective analysis of results of patch tests for DL-alpha-tocopherol sensitivity, 0.9% of patients had a definite positive reaction, while over 50% had a weakly positive, non-vesicular erythematous reaction (107869).
Orally, vitamin E has been associated with pruritus in one clinical trial (34596).
Subcutaneously, vitamin E has been associated with reports of lipogranuloma (85188,112331). In one case, subcutaneous injection of a specific supplement (1Super Extenze), containing mineral oil and tocopherol acetate, into the penile tissue resulted in penile disfigurement due to sclerosing lipogranuloma (85188). In another case, a 50-year-old Iranian female presented with lipogranuloma of the face, characterized by severe facial erythema, edema, and tenderness, 3 months after receiving subcutaneous injections of vitamin E to the cheeks for "facial rejuvenation." The patient had noticed initial symptoms within 3 days, and her symptoms progressively worsened over time (112331).
Gastrointestinal ...Orally, vitamin E supplementation has been associated with abdominal pain, nausea, diarrhea, or flu-like symptoms (85040,85323). Intravenously, large doses of vitamin E in premature infants are associated with an increased risk of necrotizing enterocolitis and sepsis (85083,85231).
Genitourinary ...There is contradictory evidence about the effect of vitamin E on prostate cancer risk. One large-scale population study shows that males who take a multivitamin more than 7 times per week and who also take a separate vitamin E supplement have a significantly increased risk of developing prostate cancer (15607). In a large-scale clinical trial (The SELECT trial) in males over the age of 50 years, taking all-rac-alpha-tocopherol (synthetic vitamin E) 400 IU daily increased the risk of developing prostate cancer by 17% when compared with placebo. However, the difference in prostate cancer risk between vitamin E and placebo became significant only 3 years after patients stopped taking supplementation and were followed in an unblinded fashion. Interestingly, patients taking vitamin E plus selenium did not have a significantly increased risk of prostate cancer (17688).
Hematologic ...High doses of vitamin E might increase the risk of bleeding due to antagonism of vitamin K-dependent clotting factors and platelet aggregation. Patients with vitamin K deficiencies or taking anticoagulant or antiplatelet drugs are at a greater risk for bleeding (4098,4844,11999,34596,34538,34626,34594,112162).
Neurologic/CNS ...There is concern that vitamin E might increase the risk of hemorrhagic stroke (16708,34594,34596,108641). In one clinical study, there was a higher incidence of hemorrhagic stroke in male smokers taking all-rac-alpha-tocopherol (synthetic vitamin E) for 5-8 years compared to those not taking vitamin E (3949). Other studies lasting from 1.4-4.5 years and using either all-rac-alpha-tocopherol (synthetic vitamin E) or RRR-alpha-tocopherol (natural vitamin E) showed no significantly increased risk for stroke (2307,3896,3936). A meta-analysis of studies shows that vitamin E in doses of 300-800 IU daily, including both natural and synthetic forms, does not significantly affect total stroke risk. However, it significantly increases the risk of hemorrhagic stroke by 22%. This means that there will be one additional hemorrhagic stroke for every 1250 patients taking vitamin E. In contrast to this finding, the analysis also found that vitamin E significantly reduces the risk of ischemic stroke by 10%. This means that one ischemic stroke will be prevented for every 476 patients taking vitamin E (14621). In patients with moderately severe Alzheimer disease, taking vitamin E 2000 IU for 2 years has been associated with a modest, but significant, increase in falls and episodes of syncope when compared to placebo (4635).
Pulmonary/Respiratory ...When inhaled, vitamin E acetate is thought to play a role in the development of e-cigarette, or vaping, product-use associated lung injury (EVALI). Although a causal link has not yet been determined, in two case series, vitamin E acetate has been found in most bronchoalveolar lavage samples taken from the primary site of lung injury in patients with EVALI, whereas no vitamin E was found in healthy control samples. Other ingredients, including THC or nicotine, were also commonly found in samples. However, priority toxicants including medium chain triglyceride (MCT) oil, plant oil, petroleum distillate, or terpenes, were undetectable in almost all samples. EVALI has resulted in death in some patients (101062,102970).
Other ...In an analysis of 3 trials, taking vitamin E 400 IU with vitamin C 1000 mg daily for 14-22 weeks during gestation appears to increase the risk of gestational hypertension by 30% compared to placebo in patients at risk of pre-eclampsia. However, the risk of pre-eclampsia itself was not increased (83450).
