| Ingredients | Amount Per Serving |
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(Ascorbic Acid)
(Vitamin C (Alt. Name: Ascorbic Acid) Note: from ferment media)
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250 mg |
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Immune Support Blend
(from ferment media)
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15 mg |
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(berry)
(from ferment media)
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(root)
(from ferment media)
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(Astragalus )
(root)
(from ferment media)
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Ferment Media (Form: Bromelain, Lactic Acid Bacteria (Form: Bifidobacterium bifidum Genus: Bifidobacterium Species: bifidum, Lactobacillus acidophilus Genus: Lactobacillus Species: acidophilus, Lactobacillus rhamnosus Genus: Lactobacillus Species: rhamnosus), organic Orange peel powder PlantPart: peel, organic Saccharomyces cerevisiae Genus: Saccharomyces Species: cerevisiae, organic Soy flour, Papain), organic Gum Acacia, organic Brown Rice, Silica, organic Coating (Form: organic Guar Gum, organic Palm Oil, organic Sunflower Lecithin, Tapioca Maltodextrin)
Below is general information about the effectiveness of the known ingredients contained in the product Fermented Vitamin C 250 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
INSUFFICIENT RELIABLE EVIDENCE to RATE
Below is general information about the safety of the known ingredients contained in the product Fermented Vitamin C 250 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. Doses of astragalus up to 60 grams daily for up to 4 months have been used without reported adverse effects (32920,33038,95909,114804). ...when used intravenously. Infusion of doses up to 80 grams daily for up to 4 months under the supervision of a medical professional have been used with apparent safety (32811,32812,32828,95909,114688,114804). There is insufficient reliable information available about the safety of astragalus when used topically.
PREGNANCY AND LACTATION:
There is insufficient reliable information in humans.
However, astragaloside, a constituent of astragalus, has maternal and fetal toxic effects in animals (32881). Avoid using.
LIKELY SAFE ...when used orally in the amounts typically found in foods. Elderberry has generally recognized as safe (GRAS) status in the US (4912).
POSSIBLY SAFE ...when elderberry fruit extract is used orally, short-term. One specific elderberry fruit extract (Sambucol, Nature's Way) has been used with apparent safety for up to 5 days (5260,12235,103831); another (BerryPharma, Iprona AG) has been used with apparent safety for up to 15 days (91374). A specific elderberry fruit extract lozenge (ViraBLOC, HerbalScience) has been used with apparent safety for 2 days (17022). Other elderberry fruit extracts have been used with apparent safety for up to 12 weeks (21141,21142).
POSSIBLY UNSAFE ...when elder tree leaves and stems, or unripe or uncooked elderberries, are consumed. The unripe green fruit, as well as the leaves and stems of the elder tree, contain a cyanide-producing chemical, which can cause serious toxicity (17020,17021,21143,21144,91374). Cooking eliminates the toxin.
CHILDREN: LIKELY SAFE
when consumed in the amounts typically found in foods.
CHILDREN: POSSIBLY SAFE
when used orally for up to 3 days.
A specific fruit extract (Sambucol, Nature's Way) has been used in doses of 15 mL twice daily for 3 days in children 5 years and older (5260,103831).
CHILDREN: POSSIBLY UNSAFE
when unripe or uncooked elderberries are consumed.
The unripe green fruit, as well as the leaves and stems of the elder tree, contain a cyanide-producing chemical , which can cause serious toxicity (17020,17021,21143,21144,91374). Cooking eliminates the toxin.
PREGNANCY AND LACTATION: LIKELY SAFE
when consumed in the amounts typically found in foods.
There is insufficient reliable information available about the safety of elderberry when used for medicinal purposes; avoid using in amounts greater than those found in foods.
LIKELY SAFE ...when used orally and appropriately, short-term. Eleuthero root extract 300-2000 mg has been used safely in clinical trials lasting up to 3 months (730,1427,2574,7522,11099,15586,91509). There is insufficient reliable information available about the safety of eleuthero when used long-term.
CHILDREN: POSSIBLY SAFE
when used orally in adolescents aged 12-17 years, short-term.
Eleuthero 750 mg three times daily was used for 6 weeks with apparent safety in one clinical trial (75028). There is insufficient reliable information available about the safety of eleuthero in children or adolescents when used long-term.
PREGNANCY AND LACTATION:
Insufficient reliable information available; avoid using.
LIKELY SAFE ...when used orally, topically, intramuscularly, or intravenously and appropriately. Vitamin C is safe when taken orally in doses below the tolerable upper intake level (UL). Tell patients not to exceed the UL of 2000 mg daily (1959,4713,4714,4844). ...when used intravenously or intramuscularly and appropriately. Injectable vitamin C is an FDA-approved prescription product (15) and has been used with apparent safety in clinical trials up to 150 mg/kg daily for up to 4 days (114489) and up to 200 mg/kg daily for up to 2 days (114492).
POSSIBLY UNSAFE ...when used orally in excessive doses. Doses greater than the tolerable upper intake level (UL) of 2000 mg daily can significantly increase the risk of adverse effects such as osmotic diarrhea and gastrointestinal upset (4844).
CHILDREN: LIKELY SAFE
when used orally and appropriately (4844,10352,14443).
CHILDREN: POSSIBLY UNSAFE
when used orally in excessive amounts.
Tell patients not to use doses above the tolerable upper intake level (UL) of 400 mg daily for children ages 1 to 3 years, 650 mg daily for children 4 to 8 years, 1200 mg daily for children 9 to 13 years, and 1800 mg daily for adolescents 14 to 18 years. Higher doses can cause osmotic diarrhea and gastrointestinal upset (4844).
PREGNANCY AND LACTATION: LIKELY SAFE
when used orally and appropriately (4844).
PREGNANCY AND LACTATION: POSSIBLY UNSAFE
when used orally in excessive doses.
Tell patients over age 19 not to use doses exceeding the UL of 2000 mg daily when pregnant or breast-feeding and for those 14-18 years of age not to use doses exceeding 1800 mg daily when pregnant or breast-feeding. Higher doses can cause osmotic diarrhea and gastrointestinal upset. Large doses of vitamin C during pregnancy can also cause newborn scurvy (4844); avoid using.
Below is general information about the interactions of the known ingredients contained in the product Fermented Vitamin C 250 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, taking astragalus with antidiabetes drugs might increase the risk of hypoglycemia.
 Details
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Theoretically, astragalus might interfere with cyclophosphamide therapy.
Details
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Theoretically, astragalus might interfere with immunosuppressive therapy.
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Theoretically, astragalus might increase levels and adverse effects of lithium.
Details
Animal research suggests that astragalus has diuretic properties (15103). Theoretically, due to this diuretic effect, astragalus might reduce excretion and increase levels of lithium.
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Theoretically, elderberry might interfere with immunosuppressant therapy due to its immunostimulant activity.
Details
Elderberry has immunostimulant activity, increasing the production of cytokines, including interleukin and tumor necrosis factor (10796).
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Theoretically, elderberry might interact with pazopanib, potentially increasing the risk of adverse effects.
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Theoretically, eleuthero may have antiplatelet effects and may increase the risk of bleeding if used with anticoagulant or antiplatelet drugs.
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Theoretically, eleuthero might have additive effects when used with antidiabetes drugs.
Details
Animal research suggests that certain constituents of eleuthero have hypoglycemic activity in both healthy and diabetic animals (7591,73535,74932,74956,74988,74990). A small study in adults with type 2 diabetes also shows that taking eleuthero for 3 months can lower blood glucose levels (91509). However, one very small study in healthy individuals shows that taking powdered eleuthero 3 grams, 40 minutes prior to a 75-gram oral glucose tolerance test, significantly increases postprandial blood glucose levels when compared with placebo (12536). These contradictory findings might be due to patient-specific variability and variability in active ingredient ratios.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP1A2.
Details
In vitro and animal research suggest that standardized extracts of eleuthero inhibit CYP1A2 (7532). This effect has not been reported in humans.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP2C9.
Details
In vitro and animal research suggest that standardized extracts of eleuthero might inhibit CYP2C9 (7532). This effect has not been reported in humans.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP2D6.
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Theoretically, eleuthero might increase levels of drugs metabolized by CYP3A4.
Details
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Eleuthero might increase serum digoxin levels and increase the risk of side effects.
Details
In one case report, a 74-year-old male who was stabilized on digoxin presented with an elevated serum digoxin level after starting an eleuthero supplement, without symptoms of toxicity. After stopping the supplement, serum digoxin levels returned to normal (543). It is not clear whether this was due to a pharmacokinetic interaction or to interference with the digoxin assay (15585). Although the product was found to be free of digoxin and digitoxin (543), it was not tested for other contaminants (797).
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Theoretically, eleuthero might interfere with immunosuppressive drugs because of its immunostimulant activity.
Details
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Theoretically, eleuthero might decrease levels of drugs metabolized by OATP.
Details
In vitro research suggests that eleuthero inhibits OATP2B1, which might reduce the bioavailability of oral drugs that are substrates of OATP2B1 (35450). Due to the weak inhibitory effect identified in this study, this interaction is not likely to be clinically significant.
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Theoretically, eleuthero might increase levels of P-glycoprotein substrates.
Details
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High-dose vitamin C might slightly prolong the clearance of acetaminophen.
Details
A small pharmacokinetic study in healthy volunteers shows that taking high-dose vitamin C (3 grams) 1.5 hours after taking acetaminophen 1 gram slightly increases the apparent half-life of acetaminophen from around 2.3 hours to 3.1 hours. Ascorbic acid competitively inhibits sulfate conjugation of acetaminophen. However, to compensate, elimination of acetaminophen glucuronide and unconjugated acetaminophen increases (6451). This effect is not likely to be clinically significant.
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Theoretically, antioxidant effects of vitamin C might reduce the effectiveness of alkylating agents.
Details
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs that generate free radicals, such as cyclophosphamide, chlorambucil, carmustine, busulfan, and thiotepa (391). In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells (14012,14013). More evidence is needed to determine what effect, if any, antioxidants such as vitamin C have on chemotherapy.
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Vitamin C can increase the amount of aluminum absorbed from aluminum compounds.
Details
Research in animals and humans shows that vitamin C increases aluminum absorption, theoretically by chelating aluminum and keeping it in solution where it is available for absorption (10549,10550,10551,21556). In people with normal renal function, urinary excretion of aluminum will likely increase, making aluminum retention and toxicity unlikely (10549). Patients with renal failure who take aluminum-containing compounds such as phosphate binders should avoid vitamin C supplements in doses above the recommended dietary allowances.
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Theoretically, the antioxidant effects of vitamin C might reduce the effectiveness of antitumor antibiotics.
Details
The use of antioxidants like vitamin C during chemotherapy is controversial. There is concern that antioxidants could reduce the activity of chemotherapy drugs which generate free radicals, such as doxorubicin (391). In contrast, some researchers theorize that antioxidants might make chemotherapy more effective by reducing oxidative stress that could interfere with apoptosis (cell death) of cancer cells (14012,14013). More evidence is needed to determine what effects, if any, antioxidants such as vitamin C have on chemotherapy.
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Acidification of the urine by vitamin C might increase aspirin levels.
Details
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels (3046). However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion (10588,10589), suggesting this interaction is not clinically significant.
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Acidification of the urine by vitamin C might increase choline magnesium trisalicylate levels.
Details
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels (3046,4531). However, short-term use of up to 6 grams daily of vitamin C does not seem to affect urinary pH or salicylate excretion (10588,10589), suggesting this interaction probably is not clinically significant.
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Vitamin C might increase blood levels of estrogens.
Details
Increases in plasma estrogen levels of up to 55% occur under some circumstances when vitamin C is taken concurrently with oral contraceptives or hormone replacement therapy, including topical products (129,130,11161). It is suggested that vitamin C prevents oxidation of estrogen in the tissues, regenerates oxidized estrogen, and reduces sulfate conjugation of estrogen in the gut wall (129,11161). When tissue levels of vitamin C are high, these processes are already maximized and supplemental vitamin C does not have any effect on estrogen levels. Increases in plasma estrogen levels may occur when patients who are deficient in vitamin C take supplements (11161). Monitor these patients for estrogen-related side effects.
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Theoretically, vitamin C might decrease levels of fluphenazine.
Details
In one patient there was a clinically significant decrease in fluphenazine levels when vitamin C (500 mg twice daily) was started (11017). The mechanism is not known, and there is no further data to confirm this interaction.
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Vitamin C can modestly reduce indinavir levels.
Details
One pharmacokinetic study shows that taking vitamin C 1 gram orally once daily along with indinavir 800 mg orally three times daily reduces the area under the concentration-time curve of indinavir by 14%. The mechanism of this interaction is unknown, but it is unlikely to be clinically significant in most patients. The effect of higher doses of vitamin C on indinavir levels is unknown (11300,93578).
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Vitamin C can increase levothyroxine absorption.
Details
Two clinical studies in adults with poorly controlled hypothyroidism show that swallowing levothyroxine with a glass of water containing vitamin C 500-1000 mg in solution reduces thyroid stimulating hormone (TSH) levels and increases thyroxine (T4) levels when compared with taking levothyroxine alone. This suggests that vitamin C increases the oral absorption of levothyroxine, possibly due to a reduction in pH (102978).
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Vitamin C might decrease the beneficial effects of niacin on high-density lipoprotein (HDL) cholesterol levels.
Details
A combination of niacin and simvastatin (Zocor) effectively raises HDL cholesterol levels in patients 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% in patients with coronary disease (7388,11537). It is not known whether this adverse effect is due to a single antioxidant such as vitamin C, or to the combination. It also is not known whether it will occur in other patient populations.
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Acidification of the urine by vitamin C might increase salsalate levels.
Details
It has been suggested that acidification of the urine by vitamin C could increase reabsorption of salicylates by the renal tubules, and increase plasma salicylate levels (3046). However, short-term use of up to 6 grams/day vitamin C does not seem to affect urinary pH or salicylate excretion (10588,10589), suggesting this interaction probably is not clinically significant.
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High-dose vitamin C might reduce the levels and effectiveness of warfarin.
Details
Vitamin C in high doses may cause diarrhea and possibly reduce warfarin absorption (11566). There are reports of two people who took up to 16 grams daily of vitamin C and had a reduction in prothrombin time (9804,9806). Lower doses of 5-10 grams daily can also reduce warfarin absorption. In many cases, this does not seem to be clinically significant (9805,9806,11566,11567). However, a case of warfarin resistance has been reported for a patient who took vitamin C 500 mg twice daily. Cessation of vitamin C supplementation resulted in a rapid increase in international normalized ratio (INR) (90942). Tell patients taking warfarin to avoid taking vitamin C in excessively high doses (greater than 10 grams daily). Lower doses may be safe, but the anticoagulation activity of warfarin should be monitored. Patients who are stabilized on warfarin while taking vitamin C should avoid adjusting vitamin C dosage to prevent the possibility of warfarin resistance.
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Below is general information about the adverse effects of the known ingredients contained in the product Fermented Vitamin C 250 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 intravenously, astragalus root seems to be well tolerated.
Topically, no adverse effects have been reported. However, a thorough evaluation of safety outcomes has not been conducted.
Serious Adverse Effects (Rare):
Orally: A case report raises concerns about liver and kidney cysts with astragalus use.
Cardiovascular ...Orally, astragalus has reportedly been associated with lacunar angina in one clinical trial. However, this may not have been caused by astragalus (17355). In addition, rapid intravenous administration of astragalus has resulted in temporary palpitations (32812).
Dermatologic ...Intravenously, astragalus may cause rash, eczema, and pruritus (33034).
Gastrointestinal ...Orally, astragalus has reportedly been associated with enterocolitis and nausea in one clinical trial. However, these effects may not have been caused by astragalus (17355).
Genitourinary ...Orally, astragalus has reportedly been associated with vulvitis in one clinical trial. However, this effect may not have been caused by astragalus (17355).
Hepatic ...A case of high serum CA19-9 levels and small liver and kidney cysts has been reported for a 38-year-old woman who drank astragalus tea daily for one month. Levels returned to normal after one month, and cysts disappeared after ten months. Both symptoms returned following a resumption of astragalus use. The authors state that astragalus was the likely cause given the temporal relationship (90658).
Musculoskeletal ...Orally, astragalus has been associated with reports of musculoskeletal pain in one clinical trial. However, these effects may not have been caused by astragalus (114803).
Neurologic/CNS ...Intravenously, administration of astragalus has been associated with temporary dizziness in patients with heart failure in clinical research (32812,114804). Orally, astragalus has also been associated with dizziness in one clinical study. However, these effects may not have been caused by astragalus (114803).
Pulmonary/Respiratory ...Orally, astragalus has reportedly been associated with rhinosinusitis and pharyngitis in one clinical trial. However, these effects may not have been caused by astragalus (17355).
Renal ...A case of high serum CA19-9 levels and small liver and kidney cysts has been reported for a 38-year-old woman who drank astragalus tea daily for one month. Levels returned to normal after one month, and cysts disappeared after ten months. Both symptoms returned following a resumption of astragalus use. The authors state that astragalus was the likely cause given the temporal relationship (90658).
General
...Orally, elderberry extracts prepared from ripe fruit seem to be well tolerated.
Most Common Adverse Effects:
Orally: When adverse effects occur, they are likely due to ingestion of raw and unripe elderberries, or seeds, leaves, and other plant parts. Due to cyanogenic glycosides, these may cause nausea, vomiting, severe diarrhea, weakness, dizziness, numbness, and stupor. Cooking eliminates the toxin.
Gastrointestinal
...Orally, nausea and vomiting have been reported after consuming a specific elderberry and echinacea product
Vogel Bioforce AG) (95650). However, it is unclear if this was due to the elderberry or Echinacea contained in the product.
Raw and unripe elderberries, and the seeds, leaves, and other elder tree parts might cause nausea, vomiting, or severe diarrhea due to cyanogenic glycosides (17020,17021). Cooking eliminates the toxin.
Hepatic ...In one case report, a 60-year-old female with underlying autoimmune disease presented with autoimmune hepatitis after taking elderberry at an unknown dose for several years. The patient presented with nausea, jaundice, abdominal pain, and abdominal distention. Liver function tests returned to baseline 4 weeks after initiating treatment with prednisone 40 mg daily and discontinuing elderberry (110123).
Immunologic ...Elder tree pollen might cause an allergic reaction characterized by rhinitis and dyspnea in some patients who are allergic to grass pollen. These patients might also experience an allergic reaction to elderberry extracts (11095).
Neurologic/CNS ...Raw and unripe elderberries might cause weakness, dizziness, numbness, and stupor due to cyanogenic glycosides (17020,17021). Cooking eliminates the toxin.
General
...Orally, eleuthero root is generally well tolerated when used short-term.
Most Common Adverse Effects:
Orally: Diarrhea, dyspepsia, gastrointestinal upset, headache, nausea, and urticaria.
Cardiovascular ...Orally, increased blood pressure has been reported in children with hypotension taking eleuthero in one clinical study (74980). Eleuthero has been reported to cause tachycardia, hypertension, and pericardial pain in patients with rheumatic heart disease or atherosclerosis. It is unclear if these effects were caused by eleuthero, or by the cardioglycoside-containing herb, silk vine (Periploca sepium), which is a common adulterant found in eleuthero products (12,797,6500).
Dermatologic ...Orally, eleuthero has been reported to cause rash in some clinical studies (75013,75028).
Gastrointestinal ...Orally, eleuthero has been reported to cause dyspepsia, nausea, diarrhea, and gastrointestinal upset in some patients (74938,75028,91510).
Genitourinary ...Orally, mastalgia and uterine bleeding were reported in 7. 3% of females taking eleuthero 2 grams daily in one clinical study (6500,11099). These adverse effects seem to be more likely with higher doses.
Neurologic/CNS
...Orally, headaches have been reported in 9.
8% of people taking eleuthero in one clinical study (11099).
In one case report, a 53-year-old female developed spontaneous subarachnoid hemorrhage associated with the use of an herbal supplement containing red clover, dong quai, and eleuthero (70419). It is unclear if this event was related to the use of eleuthero, the other ingredients, the combination, or another cause entirely.
Psychiatric ...Orally, nervousness has been reported in 7. 3% of people taking eleuthero in one clinical study (11099). Eleuthero has also been reported to cause slight anxiety, irritability, and melancholy in some patients (6500,11099). These adverse effects seem to be more likely to occur with higher doses.
General
...Orally, intravenously, and topically, vitamin C is well-tolerated.
Most Common Adverse Effects:
Orally: Abdominal cramps, esophagitis, heartburn, headache, osmotic diarrhea, nausea, vomiting. Kidney stones have been reported in those prone to kidney stones. Adverse effects are more likely to occur at doses above the tolerable upper intake level of 2 grams daily.
Topically: Irritation and tingling.
Serious Adverse Effects (Rare):
Orally: There have been rare case reports of carotid inner wall thickening after large doses of vitamin C.
Intravenously: There have been case reports of hyperoxalosis and oxalate nephropathy following high-dose infusions of vitamin C.
Cardiovascular
...Evidence from population research has found that high doses of supplemental vitamin C might not be safe for some people.
In postmenopausal adults with diabetes, supplemental vitamin C intake in doses greater than 300 mg per day is associated with increased risk of cardiovascular mortality. However, dietary intake of vitamin C is not associated with this risk. Also, vitamin C intake is not associated with an increased risk of cardiovascular mortality in patients without diabetes (12498).
Oral supplementation with vitamin C has also been associated with an increased rate of carotid inner wall thickening in men. There is preliminary evidence that supplemental intake of vitamin C 500 mg daily for 18 months can cause a 2.5-fold increased rate of carotid inner wall thickening in non-smoking men and a 5-fold increased rate in men who smoked. The men in this study were 40-60 years old (1355). This effect was not associated with vitamin C from dietary sources (1355).
There is also some concern that vitamin C may increase the risk of hypertension in some patients. A meta-analysis of clinical research suggests that, in pregnant patients at risk of pre-eclampsia, oral intake of vitamin C along with vitamin E increases the risk of gestational hypertension (83450). Other clinical research shows that oral intake of vitamin C along with grape seed polyphenols can increase both systolic and diastolic blood pressure in hypertensive patients (13162). Three cases of transient hypotension and tachycardia during intravenous administration of vitamin C have also been reported (114490).
Dental ...Orally, vitamin C, particularly chewable tablets, has been associated with dental erosion (83484).
Dermatologic ...Topically, vitamin C might cause tingling or irritation at the site of application (6166). A liquid containing vitamin C 20%, red raspberry leaf cell culture extract 0.0005%, and vitamin E 1% (Antioxidant and Collagen Booster Serum, Max Biocare Pty Ltd.) has been reported to cause mild tingling and skin tightness (102355). It is unclear if these effects are due to vitamin C, the other ingredients, or the combination.
Gastrointestinal ...Orally, the adverse effects of vitamin C are dose-related and include nausea, vomiting, esophagitis, heartburn, abdominal cramps, gastrointestinal obstruction, and diarrhea. Doses greater than the tolerable upper intake level (UL) of 2000 mg per day can increase the risk of adverse effects such as osmotic diarrhea and severe gastrointestinal upset (3042,4844,96707,104450,114493,114490). Mineral forms of vitamin C, such as calcium ascorbate (Ester-C), seem to cause fewer gastrointestinal adverse effects than regular vitamin C (83358). In a case report, high dose intravenous vitamin C was associated with increased thirst (96709).
Genitourinary ...Orally, vitamin C may cause precipitation of urate, oxalate, or cysteine stones or drugs in the urinary tract (10356). Hyperoxaluria, hyperuricosuria, hematuria, and crystalluria have occurred in people taking 1 gram or more per day (3042,90943). Supplemental vitamin C over 250 mg daily has been associated with higher risk for kidney stones in males. There was no clear association found in females, but the analysis might not have been adequately powered to evaluate this outcome (104029). In people with a history of oxalate kidney stones, supplemental vitamin C 1 gram per day appears to increase kidney stone risk by 40% (12653). A case of hematuria, high urine oxalate excretion, and the presence of a ureteral stone has been reported for a 9-year-old male who had taken about 3 grams of vitamin C daily since 3 years of age. The condition resolved with cessation of vitamin C intake (90936).
Hematologic ...Prolonged use of large amounts of vitamin C can result in increased metabolism of vitamin C; subsequent reduction in vitamin C intake may precipitate the development of scurvy (15). In one case, a patient with septic shock and a large intraperitoneal hematoma developed moderate hemolysis and increased methemoglobin 12 hours after a high-dose vitamin C infusion. The patient received a blood transfusion and the hemolysis resolved spontaneously over 48 hours (112479).
Neurologic/CNS ...Orally, the adverse effects of vitamin C are dose-related and include fatigue, headache, insomnia, and sleepiness (3042,4844,83475,83476).
Renal ...Hyperoxalosis and oxalate nephropathy have been reported following high-dose infusions of vitamin C. Hyperoxalosis and acute kidney failure contributed to the death of a 76-year-old patient with metastatic adenocarcinoma of the lung who received 10 courses of intravenous infusions containing vitamins, including vitamin C and other supplements over a period of 1 month. Dosages of vitamin C were not specified but were presumed to be high-dose (106618). In another case, a 34-year-old patient with a history of kidney transplant and cerebral palsy was found unresponsive during outpatient treatment for a respiratory tract infection. The patient was intubated for acute hypoxemic respiratory failure, initiated on vasopressors, hydrocortisone, and antibacterial therapy, and received 16 doses of vitamin C 1.5 grams. Serum creatinine level peaked at greater than 3 times baseline and the patient required hemodialysis for oliguria and uncontrolled acidosis. Kidney biopsy revealed oxalate nephropathy with concomitant drug-induced interstitial nephritis (106625). In another case, a 41-year-old patient with a history of kidney transplant presented with fever, nausea, and decreased urine output 4 days after receiving intravenous vitamin C 7 grams for urothelial carcinoma. Serum creatinine levels increased from 1.7 mg/dL to 7.3 mg/dL over those 4 days, and hemodialysis was initiated 3 days after admission due to anuria. Renal biopsy confirmed the diagnosis of acute oxalate nephropathy (109962).
Other ...Intravenously, hypernatremia and falsely elevated ketone levels is reported in a patient with septic shock and chronic kidney disease after a high-dose vitamin C infusion. The hypernatremia resolved over 24 hours after cessation of the infusion (112479).
