Interactions on record — worth a quick check against your medications. Based on 5 of 6 ingredients. Check your meds →
Dietary supplement

H Factors Ingredients & Drug Interactions

by Higher Nature

Capsule Category: Other Combinations
Most serious interaction: Moderate
The interaction bottom line Most serious interaction: Moderate

H Factors is a dietary supplement by Higher Nature with 6 active ingredients. Its ingredients are commonly taken for preventing neural tube birth defects, treating or preventing folate deficiency, supporting pregnancy health.Based on those ingredients, 303 medications have a known interaction with it, the most serious rated moderate. The ingredients most likely to interact are Vitamin B6, Zinc, Folic Acid. Use the checker below to test your specific medication, or read the full HelloPharmacist Interaction Report.

HelloPharmacist Scorecard of H Factors by Higher Nature

Our pharmacy team’s full take, with four database checks built into the cards below — a summary of what is known, not a grade of the product itself.

From our pharmacy team — supplement deep dive

What’s inside

Full disclosure
Ingredient Transparency · database check
Full

Every active ingredient lists its own amount on the label.

Why this rating?
  • The label discloses an exact amount for 7 of its 7 active ingredients.
  • “Vitamin B6” is listed as a grouped ingredient — the label gives one combined amount (50 mg) without saying how much of each component you get.

H Factors contains 7 active ingredients: folic acid, zinc, vitamin B6, riboflavin, vitamin B12, pyridoxine hydrochloride, and pyridoxal 5-phosphate. These are B vitamins and minerals that support energy metabolism, nerve function, and red blood cell formation.

The product also contains several inactive ingredients—betaine monohydrate, capsule material, titanium dioxide, chlorophyllin, lithothamnion calcarea, magnesium stearate, and silicon dioxide—which are fillers and binders that help form and stabilize the capsule.

Does it work?

Strong evidence
Evidence for Intended Use · database check
By FDA rules, dietary supplements can’t claim to treat, cure, or prevent disease — so labels speak in careful marketing language. We discern each product’s intended use from its name, label claims, and label statements, then grade the clinical evidence for that use. How these ratings are computed
Strong

Clinical evidence supports at least one of this product's ingredients for its stated purpose.

Why this rating?
  • The label markets this product for: support healthy homocysteine and heart levels.
  • We looked for evidence on: Cardiovascular disease (CVD), Atherosclerosis, Hyperhomocysteinemia, Coronary artery disease, Heart health.
  • The strongest evidence on file: Vitamin B6 is rated "Likely Effective" for Hyperhomocysteinemia (Natural Medicines).
  • Also on file: Vitamin B12 is rated "Possibly Effective" for Hyperhomocysteinemia.
  • Also on file: Vitamin B12 is rated "Insufficient Reliable Evidence To Rate" for Atherosclerosis, Cardiovascular disease (CVD).

Folic acid in this product is effective for folate deficiency and likely effective for reducing methotrexate toxicity and preventing neural tube birth defects; it's possibly effective for depression, phenytoin-related gum overgrowth, and cognitive impairment. Zinc is effective for zinc deficiency and likely effective for Wilson disease; it's possibly effective for acne, age-related macular degeneration, and diabetes.

Vitamin B6 (pyridoxine and pyridoxal 5-phosphate) is effective for sideroblastic anemia, vitamin B6 deficiency, and pyridoxine-dependent epilepsy; it's likely effective for high homocysteine and possibly effective for pregnancy-related nausea and vomiting. Riboflavin and vitamin B12 effectiveness ratings are not established in the data we hold.

We could not check Tri-Methyl Glycine.

The evidence, ingredient by ingredient Folic Acid Zinc Vitamin B6 Riboflavin Vitamin B12

How safe is it?

Well-documented data
Safety Information · database check
Well characterized

Adverse-effect, pregnancy, and general safety data are on file for most of these ingredients.

Why this rating?
  • We hold adverse-effect (side-effect) data for 5 of the 5 matched ingredients.
  • Pregnancy & breastfeeding safety ratings cover 5 of 5.
  • General safety write-ups exist for 5 of 5.
  • Remember: this measures how much safety information exists. Thin data is not the same as being safe.

Folic acid is generally safe at recommended doses for most adults and is recommended during pregnancy at standard prenatal doses to help prevent birth defects. It's considered safe while breastfeeding at normal recommended amounts.

At doses below 5 mg daily, it's well tolerated; at 5 mg daily or higher, some people report abdominal cramps, diarrhea, and rash, and at 15 mg daily, confusion, hyperactivity, impaired judgment, nausea, and sleep disturbances can occur. Folic acid use late in pregnancy has been associated with increased asthma risk in childhood, though use before or early in pregnancy has not.

Zinc is generally safe in recommended amounts, but high doses can be harmful; amounts within daily recommended needs are acceptable, but avoid high doses without medical advice. Common side effects include abdominal cramps, diarrhea, metallic taste, nausea, and vomiting.

Vitamin B6 (pyridoxine and pyridoxal 5-phosphate) is safe at normal amounts from food and standard supplements, but high doses over time can harm nerves; doses exceeding 1,000 mg daily or higher total doses carry most risk for sensory neuropathy. Riboflavin is very safe; excess is removed in urine, though dose-related nausea and bright yellow urine can occur at high doses.

Vitamin B12 is generally very safe with no established upper limit; excess is removed in urine.

Side effects, ingredient by ingredient Folic Acid Zinc Vitamin B6 Riboflavin Vitamin B12

Meds to double-check

Moderate interaction found
Known Interaction Concern · database check
Moderate identified

The most serious documented interaction for these ingredients is Moderate. Check your medications for a personalized result.

Why this rating?
  • 5 of the 5 matched ingredients can interact with medications — Vitamin B12, Vitamin B6, Riboflavin, Zinc, Folic Acid.
  • The most serious interaction on file is rated Moderate.
  • Some involve high-stakes drug classes: Parkinson's medications.
  • For scale: 303 individual medications appear in the full list. A big number alone doesn't make a product dangerous — what matters is whether YOUR medication is on it, so run yours through the interaction checker on this page.

Before taking H Factors, double-check with your doctor or pharmacist if you use seizure medications (phenobarbital, phenytoin, or primidone), as folic acid and vitamin B6 may interfere with their effectiveness. Also confirm if you're on cancer medications (capecitabine, 5-fluorouracil, methotrexate), antibiotics (quinolones, tetracyclines, cephalexin), methotrexate, penicillamine, blood pressure drugs, amiodarone, levodopa, pyrimethamine, ritonavir, integrase inhibitors, cisplatin, or metformin.

No interactions are documented for the ingredients we could check beyond those listed.

Check your own medication Run your meds through the checker above

The bottom line

Scorecard at a glanceFully disclosed formula with clinical evidence supporting its stated purpose. Moderate medication interactions have been identified, and safety information is well characterized.

H Factors is a B-complex and mineral blend useful if you're deficient in folate, zinc, or B vitamins, or if you're looking to support energy and red blood cell health. If you take seizure medications, antibiotics, cancer drugs, blood pressure medications, or metformin, talk with your doctor or pharmacist before starting this product—the interaction potential is real and worth a personalized review.

The same goes if you're pregnant and considering high-dose folic acid beyond standard prenatal amounts. Overall, it's well tolerated at recommended doses.

Educational only — not medical advice; always confirm with your pharmacist. Our editorial policy · How we use AI

Assessment coverage: 6 of 7 active ingredients matched to our full ingredient reviews (monographs). Based on the product label dated Jun 24, 2020.

This Scorecard evaluates available label information, ingredient evidence, and known medication-safety considerations. It does not independently verify product identity, purity, potency, contamination, or manufacturing quality. How these ratings are computed

At a glance

General information

Key facts about H Factors, straight from the product label.

Brand Higher Nature
Barcode (UPC) 5031013102790
Net contents 60 Capsule(s)
Market status On market
Date entered into DSLD Jun 24, 2020
DSLD ID 224695
Product type Other Combinations
Supplement form Capsule
Dietary claims / uses Nutrient, All Other, Structure/Function
Intended target group(s) Vegan, Vegetarian, Adult (18 - 50 Years), Gluten Free, Dairy Free
From the label
Everything in this section is reproduced from the manufacturer’s own product label — it’s the label speaking, not HelloPharmacist. We show it so you can see exactly what the maker states; we don’t verify or endorse those statements.

Supplement Facts

The label details for H Factors by Higher Nature, sourced from the NIH Dietary Supplement Label Database.

Supplement Facts

Daily Value (DV) Target Group(s):
Adults and children 4 or more years of age
Minimum serving Sizes:
1 Capsule(s)
Maximum serving Sizes:
4 Capsule(s)
UPC/BARCODE
5031013102790
IngredientAmount% DV
Folic Acid400 mcg200%
Zinc10 mg100%
Vitamin B650 mg3572%
Riboflavin15 mg1071%
Vitamin B12500 mcg20000%
Pyridoxine Hydrochloride15 mg--
Pyridoxal 5-Phosphate35 mg--
Tri-Methyl Glycine750 mg--

Other ingredients: Betaine Monohydrate, Capsule, Titanium Dioxide, Chlorophyllin, natural Lithothamnion calcarea, Vitamin B6, Zinc Citrate, Magnesium Stearate, Silicon Dioxide, Vitamin B6, Vitamin B2

Tap any ingredient to jump to its full detail below.

Label statements
These statements are the manufacturer’s wording, reproduced from the product label — the label is saying it, not HelloPharmacist. We don’t verify or endorse them.
General Statements

NRV = Nutrient Reference Value

This product has not been tested on animals.

Formulation

Free From: Artificial colours, flavourings or preservatives, dairy products, gluten, lactose, salt, soya, wheat, yeast.

Body health Advanced formula Optimal benefit

Vegetarian and vegan

Formula

Homocysteine & heart nutrients

Vitamins B6 and B12, folic acid and TMG help support healthy homocysteine levels

FDA Statement of Identity

Food Supplement

Suggested/Recommended/Usage/Directions

Directions: Take 2-4 capsules a day with a meal for 12 weeks, then maintain at 1-2 capsules a day. Do not exceed recommended daily intake.

Precautions

Food supplements should not be used as a substitute for a varied and balanced diet and healthy lifestyle.

Warning: B vitamins may turn urine bright yellow - this is normal. Long term intakes of this amount of Vitamin B6 may lead to mild tingling and numbness.

Storage: Store in a cool, dry place out of reach of children.

Storage

Storage: Store in a cool, dry place out of reach of children.

See for yourself

H Factors by Higher Nature label

The label scan from the NIH Dietary Supplement Label Database. Tap to enlarge.

What’s inside

The Ingredients in H Factors by Higher Nature

These are the 6 active ingredients this product is made of. Select any to open its full monograph.

Serving size1 Capsule(s) Dosage formCapsule Amounts shown are per serving.

Most supplement products combine several ingredients, and a medication can interact with the product through any one of them. Each ingredient below shows whether it has known drug interactions.

Folic Acid

Interacts with
40 drugs
400 mcg per serving

Folic acid is the man-made form of vitamin B9 and is one of the most well-studied supplements, especially for preventing serious birth defects when ta...

Folic Acid monograph & interactions

Zinc

Interacts with
67 drugs
10 mg per serving

Zinc is an essential mineral that your body needs for immune function, wound healing, taste, and smell. Most people get enough from food, but suppleme...

Zinc monograph & interactions

Vitamin B6

Interacts with
210 drugs
50 mg per serving

Vitamin B6 (pyridoxine) is an essential water-soluble vitamin that your body needs for metabolism, brain function, and making red blood cells. It is b...

Vitamin B6 monograph & interactions

Riboflavin

Interacts with
20 drugs
15 mg per serving Form: Vitamin B2

Riboflavin (vitamin B2) is an essential nutrient your body needs to turn food into energy and to keep skin, eyes, and nerves healthy. It is generally...

Riboflavin monograph & interactions

Vitamin B12

Interacts with
20 drugs
500 mcg per serving Form: Methylcobalamin

Vitamin B12 (cobalamin) is an essential nutrient your body needs to make red blood cells, keep nerves healthy, and support DNA. Supplements are very h...

Vitamin B12 monograph & interactions

Tri-Methyl Glycine

750 mg per serving

Other (inactive) ingredients: Betaine Monohydrate, Capsule, Titanium Dioxide, Chlorophyllin, Natural Lithothamnion calcarea, Vitamin B6, Zinc Citrate, Magnesium Stearate, Silicon Dioxide, Vitamin B6, Vitamin B2. These complete the product’s ingredient list but are not active constituents.

Interaction report

H Factors by Higher Nature Drug Interactions

Want to check YOUR meds against H Factors?

Ask about interactions with your drugs in plain English — “Can I take it with lisinopril?” — and we find you the answer in seconds, ingredient by ingredient.

Go to the checker
303Drugs
276 Moderate 27 Minor

Ingredients driving the most interactions

Zinc 67

Each ingredient & the kinds of drugs it affects

For each ingredient in H Factors with known interactions, here are the types of medications they can affect. Open any type for the detail — or search your exact drug in the checker above.

Vitamin B65 drug types · 210 drugs

Amiodarone (Cordarone)

Theoretically, vitamin B6 might increase the photosensitivity caused by amiodarone.
Despite initial case reports suggesting that pyridoxine may have a protective effect against amiodarone-induced photosensitivity, preliminary clinical research suggests that pyridoxine may actually exacerbate this adverse effect.

Likelihood Possible Evidence B
Antihypertensive Drugs

Theoretically, vitamin B6 may have additive effects when used with antihypertensive drugs.
Research in hypertensive rats shows that vitamin B6 can decrease systolic blood pressure. Similarly, clinical research in patients with hypertension shows that taking high doses of vitamin B6 may reduce systolic and diastolic blood pressure, possibly by reducing plasma levels of epinephrine and norepinephrine.

Likelihood Possible Evidence B
Phenobarbital (Luminal)

High doses of vitamin B6 may reduce the levels and clinical effects of phenobarbital.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenobarbital, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenobarbital to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Phenytoin (Dilantin)

High doses of vitamin B6 may reduce the levels and clinical effects of phenytoin.
Preliminary clinical evidence suggests that vitamin B6 200 mg daily can reduce plasma levels of phenytoin, possibly by increasing metabolism. It is not known whether lower doses have any effect. Advise people taking phenytoin to avoid high doses of vitamin B6.

Likelihood Possible Evidence D
Levodopa

Vitamin B6 may increase the metabolism of levodopa when taken alone, but not when taken in conjunction with carbidopa.
Vitamin B6 (pyridoxine) enhances the metabolism of levodopa, reducing its clinical effects. However, this interaction does not occur when carbidopa is used concurrently with levodopa (Sinemet). Therefore, it is not likely to be a problem in most people.

Likelihood Unlikely Evidence D

Zinc10 drug types · 67 drugs

Bictegravir/Emtricitabine/Tenofovir Alafenamide (Biktarvy)

Theoretically, zinc might decrease levels of bictegravir/emtricitabine/tenofovir alafenamide by reducing its absorption.
Advise patients that bictegravir/emtricitabine/tenofovir alafenamide should be taken at least 2 hours before or 6 hours after zinc containing products.

Likelihood Probable Evidence D
Cephalexin (Keflex)

Zinc might decrease cephalexin levels by chelating with cephalexin in the gut and preventing its absorption.
A pharmacokinetic study shows that zinc sulfate 250 mg taken concomitantly with cephalexin 500 mg decreases peak levels of cephalexin by 31% and reduces the exposure to cephalexin by 27%. Also, taking zinc sulfate 3 hours before cephalexin decreases peak levels of cephalexin by 11% and reduces the exposure to cephalexin by 18%. By decreasing cephalexin levels, zinc might increase the risk of treatment failure. This effect does not occur when zinc is taken 3 hours after the cephalexin dose. To avoid an interaction, advise patients take zinc sulfate 3 hours after taking cephalexin.

Likelihood Probable Evidence B
Cisplatin (Platinol-Aq)

Theoretically, zinc might interfere with the therapeutic effects of cisplatin.
Animal research suggests that zinc stimulates tumor cell production of the protein metallothionein, which binds and inactivates cisplatin. It is not known whether zinc supplements or high dietary zinc intake can cause clinically significant interference with cisplatin therapy. Cisplatin might also increase zinc excretion.

Likelihood Possible Evidence D
Integrase Inhibitors

Theoretically, taking zinc along with integrase inhibitors might decrease the levels and clinical effects of these drugs.
Zinc is a divalent cation. Pharmacokinetic studies have shown that other divalent cations such as calcium and iron can decrease blood levels of the integrase inhibitor dolutegravir through chelation.

Likelihood Possible Evidence D
Penicillamine (Cuprimine, Depen)

Zinc might reduce the levels and clinical effects of penicillamine.
By forming an insoluble complex with penicillamine, zinc interferes with penicillamine absorption and activity. Zinc supplements reduce the efficacy of low-dose penicillamine (0.5-1 gram/day), but do not seem to affect higher doses (1-2.75 gram/day), provided dosing times are separated. Advise patients to take zinc and penicillamine at least 2 hours apart.

Likelihood Probable Evidence B
Quinolone Antibiotics

Zinc can decrease the levels and clinical effects of quinolones antibiotics.
Quinolones form complexes with zinc in the gastrointestinal tract, reducing absorption of both the quinolone and zinc if taken at the same time. Advise patients to take these drugs at least 2 hours before, or 4-6 hours after, zinc supplements.

Likelihood Probable Evidence B
Ritonavir (Norvir)

Zinc modestly reduces levels of ritonavir.
Clinical research shows that zinc might reduce serum ritonavir levels by chelating with ritonavir in the gut and preventing its absorption. In patients with HIV, ritonavir is taken with atazanavir to prevent the metabolism and increase the effects of atazanavir. A pharmacokinetic study shows that, in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate (Solvazinc tablets) 125 mg as a single dose or as multiple daily doses for 2 weeks reduces plasma levels of ritonavir by about 16%. However, atazanavir levels still remains high enough to prevent HIV virus replication. Therefore, the decrease in ritonavir levels is not likely to be clinically significant.

Likelihood Probable Evidence B
Tetracycline Antibiotics

Zinc might reduce levels of tetracycline antibiotics.
Tetracyclines form complexes with zinc in the gastrointestinal tract, which can reduce absorption of both the tetracycline and zinc when taken at the same time. Taking zinc sulfate 200 mg with tetracycline reduces absorption of the antibiotic by 30% to 40%. Demeclocycline and minocycline cause a similar interaction. However, doxycycline does not seem to interact significantly with zinc. Advise patients to take tetracyclines at least 2 hours before, or 4-6 hours after, zinc supplements to avoid any interactions.

Likelihood Probable Evidence B
Amiloride (Midamor)

Amiloride can modestly reduce zinc excretion and increase zinc levels.
Clinical research shows that amiloride can reduce urinary zinc excretion, especially at doses of 10 mg per day or more. This zinc-sparing effect can help to counteract zinc losses caused by thiazide diuretics, but it is unlikely to cause zinc toxicity at usual amiloride doses. The other potassium-sparing diuretics, spironolactone (Aldactone) and triamterene (Dyrenium), do not seem to have a zinc-sparing effect.

Likelihood Probable Evidence B
Atazanavir (Reyataz)

Zinc modestly reduces levels of atazanavir, although this effect does not seem to be clinically significant.
Clinical research shows that zinc might decrease serum atazanavir levels by chelating with atazanavir in the gut and preventing its absorption. Although a single dose of zinc sulfate (Solvazinc tablets) 125 mg orally does not affect atazanavir concentrations in patients being treated with atazanavir/ritonavir, co-administration of zinc sulfate 125 mg daily for 2 weeks reduces plasma levels of atazanavir by about 22% in these patients. However, despite this decrease, atazanavir levels still remain at high enough concentrations for the prevention of HIV virus replication.

Likelihood Probable Evidence B

Folic Acid7 drug types · 40 drugs

5-Fluorouracil

Theoretically, high doses of folic acid might increase the toxicity of 5-fluorouracil.
Increases in gastrointestinal side effects of 5-fluorouracil, such as stomatitis and diarrhea, have been described in two clinical studies when leucovorin, a form of folic acid, was administered with 5-fluorouracil.

Likelihood Possible Evidence D
Capecitabine (Xeloda)

Use of high-dose folic acid might contribute to capecitabine toxicity.
Clinical research suggests that higher serum folate levels are associated with an increased risk for moderate or severe toxicity during capecitabine-based treatment for colorectal cancer. Additionally, in one case report, taking folic acid 15 mg daily might have contributed to increased toxicity, including severe diarrhea, vomiting, edema, hand-foot syndrome, and eventually death, in a patient prescribed capecitabine.

Likelihood Possible Evidence D
Methotrexate (Trexall, Others)

Folic acid might reduce the efficacy of methotrexate as a cancer treatment when given concurrently.
Methotrexate exerts its cytotoxic effects by preventing conversion of folic acid to the active form needed by cells. There is some evidence that folic acid supplements reduce the efficacy of methotrexate in the treatment of acute lymphoblastic leukemia, and theoretically they could reduce its efficacy in the treatment of other cancers. Advise cancer patients to consult their oncologist before using folic acid supplements. In patients treated with long-term, low-dose methotrexate for rheumatoid arthritis (RA) or psoriasis, folic acid supplements can reduce the incidence of side effects, without reducing efficacy.

Likelihood Probable Evidence B
Phenobarbital (Luminal)

Folic acid might have antagonistic effects on phenobarbital and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of phenobarbital and worsening seizure control. Monitor closely for increased seizure activity.

Likelihood Probable Evidence B
Phenytoin (Dilantin)

Folic acid might reduce serum levels of phenytoin in some patients.
Folic acid may be a cofactor in phenytoin metabolism. Folic acid, in doses of 1 mg daily or more, can reduce serum levels of phenytoin in some patients. Increases in seizure frequency have been reported. If folic acid supplements are added to established phenytoin therapy, monitor serum phenytoin levels closely. If phenytoin and folic acid are started at the same time and continued together, adverse changes in phenytoin pharmacokinetics are avoided. Note that phenytoin also reduces serum folate levels.

Likelihood Probable Evidence B
Primidone (Mysoline)

Folic acid might have antagonistic effects on primidone and increase the risk for seizures.
Folic acid can have direct convulsant activity in some people, reversing the effects of primidone and worsening seizure control. Monitor closely for increased seizure activity. Note that primidone also reduces serum folate levels.

Likelihood Probable Evidence B
Pyrimethamine (Daraprim)

Folic acid might antagonize the effects of pyrimethamine.
Folic acid can antagonize the antiparasitic effects of pyrimethamine against toxoplasmosis and Pneumocystis carinii pneumonia. Folic acid doesn't antagonize the effects of pyrimethamine in the treatment of malaria, because malarial parasites cannot use exogenous folic acid. Use folinic acid as an alternative to folic acid when indicated.

Likelihood Probable Evidence D

Riboflavin1 drug type · 20 drugs

Tetracycline Antibiotics

Theoretically, taking riboflavin with tetracycline antibiotics may decrease the potency of these antibiotics.
In vitro research suggests that riboflavin may inhibit the potency of tetracycline antibiotics. It is not clear if this effect is clinically significant, as this interaction has not been reported in humans.

Likelihood Possible Evidence D

Vitamin B121 drug type · 20 drugs

Metformin (Glucophage)

Metformin, a common medication used to manage type 2 diabetes, has been associated with lower vitamin B12 levels in some individuals. Prolonged use of metformin can interfere with the absorption of B12 in the digestive system, potentially leading to a deficiency in this essential vitamin.

Likelihood Possible Evidence A
The maker

Brand information

Manufacturer and brand details for H Factors, from the product label.

Higher Nature

See all Higher Nature products
Name
Higher Nature Ltd
Street Address
10 Discovery Way
City
Horam TN21 0GE
State
East Sussex
Web Address
highernature.com
Pharmacist Counseling Corner

H Factors by Higher Nature: Common Questions

Does H Factors by Higher Nature interact with any medications?
Yes. Based on its ingredients, H Factors has a known interaction with 303 medications. Use the checker to see how it interacts with a specific drug.
How can one product interact with so many drugs?
H Factors contains 6 active ingredients, and an interaction can come from any of them. We check every ingredient, combine the results into one list per medication, and show which ingredient and mechanism is responsible.
Where does this information come from?
The product label data comes from the NIH Dietary Supplement Label Database (DSLD); the interaction data is built on the Natural Medicines database and reviewed by HelloPharmacist pharmacists.
Is H Factors safe to take during pregnancy?
Folic acid in this product is recommended during pregnancy at standard prenatal doses to help prevent birth defects. However, folic acid use late in pregnancy has been associated with increased asthma risk in childhood. Talk with your doctor about the right dose and timing for you; they can weigh the benefits of folate for birth defect prevention against the newer research on late-pregnancy use.
Is H Factors safe while breastfeeding?
Folic acid, riboflavin, and vitamin B12 in this product are considered safe at recommended amounts while breastfeeding. Zinc at normal dietary amounts is acceptable, though high-dose supplements should be avoided without medical advice. Vitamin B6 is safe at recommended amounts; avoid high doses.
What does folic acid in this product actually do?
Folic acid is effective for treating folate deficiency and is likely effective for reducing side effects of the cancer drug methotrexate and preventing neural tube birth defects like spina bifida. It's possibly helpful for depression, gum overgrowth caused by the seizure medication phenytoin, and cognitive impairment, though the evidence is weaker for those uses.
Can high doses of the B6 in this product cause nerve damage?
Yes. Vitamin B6 at doses exceeding 1,000 mg daily or very high total doses over time can cause sensory neuropathy (nerve damage affecting sensation). At normal recommended amounts, this is not a concern. Check the label to see the dose per capsule and talk with your pharmacist if you're unsure whether it's within safe limits.
What are the most common side effects of H Factors?
At recommended doses, most people tolerate it well. If you do experience side effects, folic acid and zinc may cause abdominal cramps, diarrhea, and nausea; vitamin B6 may cause headache, nausea, or heartburn; and riboflavin can cause nausea and bright yellow urine at higher doses. These are usually dose-related and minor.
Can this product interact with my antibiotics?
Yes, potentially. Zinc can reduce absorption of quinolone antibiotics, tetracyclines, and cephalexin if taken at the same time. Riboflavin may theoretically reduce tetracycline potency, though this hasn't been reported in people. Take zinc at least 2 hours before or 4–6 hours after these antibiotics to avoid interference. Check with your pharmacist about your specific antibiotic.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

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Label information is sourced from the NIH Dietary Supplement Label Database and reflects the product version on file; always read your actual product label. This page is for education only and is not a substitute for professional medical advice. Confirm with your pharmacist or doctor before combining supplements and medications.

H Factors label
Go deeper

The Full Monographs Behind H Factors’s Ingredients

Every ingredient we hold a full HelloPharmacist monograph for — uses, evidence, safety, and the complete interaction list.

Sources

Sources & How We Checked

H Factors's label data comes from the NIH Dietary Supplement Label Database; the ingredient interaction data is from the Natural Medicines database, reviewed by our pharmacists.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

The 211 references behind this product’s interaction data

Every citation that drives the interaction findings for this product’s ingredients, from the evidence-graded Natural Medicines (TRC Healthcare) database. Open an ingredient to browse its citations — links open the study on PubMed or the publisher’s site.

Folic Acid 56 references
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Duhra P. Treatment of gastrointestinal symptoms associated with methotrexate therapy for psoriasis. J Am Acad Dermatol 1993;28:466-9. PubMed
  3. Morgan SL, Baggott JE, Vaughn WH, et al. Supplementation with folic acid during methotrexate therapy for rheumatoid arthritis. A double-blind, placebo-controlled trial. Ann Intern Med 1994;121:833-41. PubMed
  4. Froscher W, Maier V, Laage M, et al. Folate deficiency, anticonvulsant drugs, and psychiatric morbidity. Clin Neuropharmacol 1995;18:165-82. PubMed
  5. Lewis DP, Van Dyke DC, Willhite LA, et al. Phenytoin-folic acid interaction. Ann Pharmacother 1995;29:726-35. PubMed
  6. Berg MJ, Stumbo PJ, Chenard CA, et al. Folic acid improves phenytoin pharmacokinetics. J Am Diet Assoc 1995;95:352-6. PubMed
  7. Berg MJ, Fincham RW, Ebert BE, et al. Phenytoin pharmacokinetics: Before and after folic acid administration. Epilepsia 1992;33:712-20. PubMed
  8. Shafer RB, Nuttall FQ. Calcium and folic acid absorption in patients taking anticonvulsant drugs. J Clin Endocrinol Metab 1975;41:1125-9. PubMed
  9. Leeb BF, Witzmann G, Ogris E, et al. Folic acid and cyanocobalamin levels in serum and erythrocytes during low-dose methotrexate therapy of rheumatoid arthritis and psoriatic arthritis patients. Clin Exp Rheumatol 1995;13:459-63.
  10. Morgan SL, Baggott JE, Lee JY, Alarcón GS. Folic acid supplementation prevents deficient blood folate levels and hyperhomocysteinemia during longterm, low dose methotrexate therapy for rheumatoid arthritis: implications for cardiovascular disease preventi
  11. Dijkmans BA. Folate supplementation and methotrexate. Br J Rheumatol 1995;34:1172-4. PubMed
  12. Segal S, Kaminski S. Drug-nutrient interactions. American Druggist 1996 Jul;42-8.
  13. Lambie DG, Johnson RH. Drugs and folate metabolism. Drugs 1985;30:145-55. PubMed
  14. Amer College of Rheumatology ad hoc committee on clinical guidelines. Guidelines for monitoring drug therapy in rheumatoid arthritis. Arthritis Rheum 1996;39:723-31. DOI
  15. Suitor CW, Bailey LB. Dietary folate equivalents: interpretation and application. J Am Diet Assoc 2000;100:88-94. PubMed
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DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

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