Each capsule contains: Evening Primrose Oil 500 mg, providing: Linoleic Acid 347 mg, Gamma-Linolenic Acid (gamma linoleic acid) 47 mg, Vitamin E 10 mg.
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Below is general information about the effectiveness of the known ingredients contained in the product Evening Primrose 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 Evening Primrose 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.
LIKELY SAFE ...when used orally and appropriately. Evening primrose oil has been used safely in doses up to 6 grams daily for up to 1 year (7566,7567,8926,12036,20512,49286,49360,109426). There is insufficient reliable information available about the safety of evening primrose oil when used topically. There is also insufficient reliable information available about the safety of evening primrose seed, flower, or leaf when used orally or topically.
CHILDREN: POSSIBLY SAFE
when evening primrose oil is used orally and appropriately, short-term.
In children up to 5 years of age, doses of evening primrose oil up to 3 grams daily have been used safely for 5 months (20512,49273), and 0.5 grams/kg daily has been used safely for 8 weeks (7570). In children up to 12 years of age, doses of 4-6 grams daily have been used safely for 3-5 months (7565,7566,20512,49286). ...when used topically and appropriately, short-term. In children 2-10 years of age, evening primrose oil has been applied to affected areas of the skin twice daily for up to 3 months (96718). There is insufficient reliable information available about the safety of evening primrose seed, flower, or leaf when used orally or topically.
PREGNANCY: POSSIBLY SAFE
when evening primrose oil is used orally and appropriately.
In small studies of evening primrose oil for pre-eclampsia, 4 grams has been used orally daily for up to 10 weeks during pregnancy with apparent safety (1409,20525). Evening primrose oil has also been used safely during the last week of pregnancy to improve cervical ripening (20524,96717), although in one retrospective case series improvement was lacking and there was a trend toward prolonged labor, increased rates of arrest of descent, and increased oxytocin requirements (1411). Evening primrose oil has also been linked to a case report of petechiae and ecchymoses in a newborn infant whose mother took a total of 6.5 grams during the week before giving birth (16303); use with caution, especially in high doses.
LACTATION: POSSIBLY SAFE
when evening primrose oil is used orally.
Supplementation with evening primrose oil during lactation results in the secretion of high levels of the constituent gamma linolenic acid into breast milk (1982); however, this fatty acid is normally present in significant amounts in breast milk (11884).
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 Evening Primrose 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, evening primrose oil may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
 Details
Evening primrose oil contains gamma linolenic acid (GLA). There is preliminary clinical evidence that GLA can reduce platelet aggregation and prolong bleeding time (1979).
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Theoretically, evening primrose may increase the levels and clinical effects of CYP2C9 substrates.
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In vitro research shows that linoleic acid, a constituent of evening primrose oil, inhibits CYP2C9 (21017).
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Theoretically, concomitant use of lithium with evening primrose oil might decrease lithium levels and effects.
Details
In a case report, a patient on a stable dose of lithium for 10 years experienced a reduction in lithium levels after taking evening primrose oil 500 mg daily. Baseline levels were 0.69 mmol/L, which decreased to 0.37 mmol/L after 2 months and 0.23 mmol/L after 3 months of use. Lithium levels increased within 6 weeks of discontinuing evening primrose oil, to 0.73 mmol/L; no clinical effects were noted (96715).
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Theoretically, evening primrose oil might increase the levels and effects of lopinavir.
Details
In a case report, an HIV patient who took evening primrose oil (Efamol) along with lopinavir/ritonavir experienced an increase in serum levels of lopinavir to 15.2 mg/L. Six weeks after discontinuing evening primrose oil, levels of lopinavir returned to the normal range of 5-10 mg/L. When re-challenged with evening primrose oil for a week, the patient's lopinavir levels increased from 6.69 to 8.11 mg/L. It is suspected that evening primrose oil increases levels of lopinavir by inhibiting cytochrome P450 3A4 (CYP3A4), which metabolizes lopinavir (93578). However, this effect has not been reported in other research.
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Theoretically, taking evening primrose oil with phenothiazines might increase the risk of convulsions.
Details
Evening primrose oil contains gamma-linolenic acid (GLA). There is some concern that taking supplements containing GLA might cause seizures, or lower the seizure threshold, when taken with phenothiazines (88187). In one report, three patients with schizophrenia who had received phenothiazines developed EEG changes suggestive of temporal lobe epilepsy after starting treatment with GLA, although none experienced an actual seizure (21013). In another report, two patients with schizophrenia who were stabilized on phenothiazines developed seizures when evening primrose oil 4 grams daily was added. One of these patients had a prior history of seizures (21010). It is unclear whether evening primrose oil had any additive epileptogenic effects with the phenothiazines; there is no evidence that taking evening primrose oil alone causes seizures (88187).
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Theoretically, GLA might increase the risk of bleeding when taken with anticoagulant or antiplatelet rugs.
Details
Animal and human research suggests that GLA reduces platelet aggregation (1979).
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Theoretically, antioxidant effects of vitamin E might reduce the effectiveness of alkylating agents.
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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.
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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.
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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.
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A specific form of vitamin E might increase absorption and levels of cyclosporine.
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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.
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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.
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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.
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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).
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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).
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Below is general information about the adverse effects of the known ingredients contained in the product Evening Primrose 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 and topically, evening primrose oil is generally well tolerated.
There is limited reliable information available regarding the safety or adverse effects of other parts of the plant.
Most Common Adverse Effects:
Orally: Abdominal pain and distention, diarrhea, dyspepsia, flatulence, nausea, and vomiting.
Dermatologic ...Orally, use of evening primrose oil has been associated with reports of skin rash and acne (9156,9794,49338). There is a case report of extensive but transient petechiae and purpuric ecchymoses in a newborn infant whose mother had consumed raspberry leaf tea and a total of 6.5 grams of evening primrose oil orally and vaginally during the week prior to delivery. The infant had a normal platelet count and no signs of hemorrhage, and was discharged healthy at 3 days of age (16303).
Gastrointestinal ...Gastrointestinal complaints, including abdominal pain, distension and fullness, nausea and vomiting, diarrhea, dyspepsia, and flatulence are the most common adverse effects of evening primrose (8926,9794,20533,49188,49286,49339,49365,65864,88184,102556). Often these effects resolve with continued use. Altered taste has also been reported (49339).
Hematologic ...There is preliminary clinical evidence that evening primrose oil can decrease platelet aggregation and prolong bleeding time. In a small study of patients with hyperlipidemia, taking evening primrose oil 3 grams daily for 4 months was associated with a 40% increase in bleeding time, and decreases in ADP- and epinephrine-induced platelet aggregation of 50% and 60% respectively (1979). There is also a case report of diffuse ecchymoses and petechiae in a neonate whose mother had consumed 6.5 grams of evening primrose oil over the week prior to delivery (16303).
Neurologic/CNS
...Cases of dizziness (9794) and headache (88184) have been reported with evening primrose oil when used orally.
There is a report of seizures in a patient taking evening primrose oil and receiving anesthesia; however, the patient was also taking other drugs and it is therefore unclear if evening primrose was the cause (613). There is also concern that evening primrose oil might cause seizures, or lower the seizure threshold, in patients with schizophrenia who are treated with phenothiazines. This is based on limited data from two studies published in the 1980s. In one report, three patients with schizophrenia who had received phenothiazines developed EEG changes suggestive of temporal lobe epilepsy after starting treatment with evening primrose, although none experienced an actual seizure (21013). In the other report, two patients with schizophrenia who were stabilized on phenothiazines developed seizures when evening primrose oil 4 grams daily was added. One of these patients had a prior history of seizures (21010). There is no evidence that evening primrose taken alone, without medications known to lower the seizure threshold, can cause seizures (88187).
Other ...Weight gain has been reported in individuals receiving evening primrose oil (49338).
General
...Orally, GLA seems to be well tolerated.
Most Common Adverse Effects:
Orally: Mild gastrointestinal adverse effects, including belching, bloating, diarrhea, dyspepsia, flatulence, nausea, and vomiting.
Gastrointestinal ...Orally, GLA may cause mild gastrointestinal effects such as dyspepsia, nausea, bloating, vomiting, soft stools, diarrhea, flatulence, and belching (7701,7702,8926,107927).
Hematologic ...Orally, GLA might prolong bleeding time (1979).
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).
