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B complex 100 side effects: B 100 Complex Side Effects: Common, Severe, Long Term

B 100 Complex Side Effects: Common, Severe, Long Term



Generic name: multivitamin

Medically reviewed by Drugs.com. Last updated on Jun 21, 2023.

Note: This document contains side effect information about multivitamin. Some dosage forms listed on this page may not apply to the brand name B 100 Complex.

Applies to multivitamin: oral capsule, oral liquid, oral tablet, oral tablet disintegrating. Other dosage forms:

  • injection injectable, injection solution, oral capsule, oral elixir, oral liquid, oral tablet, sublingual liquid
  • oral elixir, oral tablet, oral tablet extended release
  • oral capsule, oral tablet
  • oral tablet
  • oral liquid, oral solution, oral tablet chewable
  • oral capsule


If your product has iron in it:

  • Accidental overdose of drugs that have iron in them is a leading cause of deadly poisoning in children younger than 6 years of age. Keep
    away from children. If this drug is taken by accident, call a doctor or poison control center right away.

Serious side effects of B 100 Complex

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your
doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

All products:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing;
    tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue,
    or throat.

If your product has iron in it:

  • Black, tarry, or bloody stools.
  • Fever.
  • Very upset stomach or throwing up.
  • Very bad belly pain.
  • Throwing up blood or throw up that looks like coffee grounds.
  • Stomach cramps.

Other side effects of B 100 Complex

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical
help if any of these side effects or any other side effects bother you or do not go away:

All products:

  • Upset stomach or throwing up.

If your product has iron in it:

  • Constipation.
  • Change in color of stool to green.
  • Diarrhea.
  • Belly pain.

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical
advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.

Frequently asked questions

  • What is Foltanx prescribed for?

More about B 100 Complex (multivitamin)

  • Check interactions
  • Compare alternatives
  • Drug class: vitamin and mineral combinations

Patient resources

Other brands

Folbee, Vitamins, Folbic, MVI Adult, … +25 more

Professional resources

  • Prescribing Information

Related treatment guides

  • Dietary Supplementation

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Some side effects may not be reported. You may report them to the FDA.

Medical Disclaimer

B-100 Complex Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing


This product is a combination of B vitamins used to treat or prevent vitamin deficiency due to poor diet, certain illnesses, alcoholism, or during pregnancy. Vitamins are important building blocks of the body and help keep you in good health. B vitamins include thiamine, riboflavin, niacin/niacinamide, vitamin B6, vitamin B12, folic acid, and pantothenic acid.Some brands of B vitamins also contain ingredients such as vitamin C, vitamin E, biotin, or zinc. Consult your doctor or pharmacist if you have questions about the ingredients in your brand.

How to use B-100 Complex Tablet, Extended Release

Take this medication by mouth, usually once daily or as directed. Follow all directions on the product package. If you have any questions, ask your doctor or pharmacist.

If you are taking a brand that contains vitamin C, take this medication by mouth with a full glass of water (8 ounces/240 milliliters) unless your doctor directs you otherwise.

If you are taking chewable tablets, chew the tablet thoroughly before swallowing.

If you are taking extended-release capsules, swallow them whole. Do not crush or chew extended-release capsules or tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Swallow the whole tablet without crushing or chewing.

If you are taking a liquid product, use a medication-measuring device to carefully measure the dose. Do not use a household spoon. Some liquid products need to be shaken before each dose. Some products that contain vitamin B12 need to be placed under the tongue and held there before swallowing. Follow label directions carefully to get the most benefit.

Take this medication regularly in order to get the most benefit from it. To help you remember, take it at the same time each day.

Side Effects

Mild upset stomach or flushing may occur. These effects are usually temporary and may disappear as your body adjusts to this product. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

If your doctor has directed you to use this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US –

In the US – Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada – Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.


Before taking this product, tell your doctor or pharmacist if you are allergic to any of its ingredients; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

If you have any of the following health problems, consult your doctor or pharmacist before using this product: diabetes, liver problems, vitamin B12 deficiency (pernicious anemia).

Chewable tablets or liquid products may contain aspartame. If you have phenylketonuria (PKU) or any other condition that requires you to restrict your intake of aspartame (or phenylalanine), consult your doctor or pharmacist about using this drug safely.

Liquid forms of this product may contain sugar and/or alcohol. Caution is advised if you have diabetes, alcohol dependence, or liver disease. Ask your doctor or pharmacist about using this product safely.

Tell your doctor if you are pregnant before using this medication. This product is safe to take during pregnancy when used as directed. Certain spinal cord birth defects may be prevented by maintaining adequate amounts of folic acid during pregnancy. Consult your doctor or pharmacist for details.

This product passes into breast milk. While there have been no reports of harm to nursing infants, consult your doctor before breast-feeding.


Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor’s approval.

Some products that may interact with this drug are: altretamine, cisplatin, certain antibiotics (such as chloramphenicol), certain anti-seizure drugs (such as phenytoin), levodopa, other vitamin/nutritional supplements.

This product may interfere with certain lab tests (such as urobilinogen, intrinsic factor antibodies), possibly causing false test results. Make sure lab personnel and all your doctors know you use this product.

Does B-100 Complex Tablet, Extended Release interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker


If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: stomach pain, nausea, vomiting, diarrhea.

Keep all medical and lab appointments.

This product is not a substitute for a proper diet. Remember that it is best to get your vitamins from healthy foods. B vitamins are naturally found in leafy greens and other vegetables, meat, fish, poultry, and enriched breads/cereals.

If you are taking this product on a regular schedule and miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Refer to storage information printed on the package. If you have any questions about storage, ask your pharmacist. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.



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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

Today on WebMD

Vitamin B Complex | What do you need to know?

The B group or complex of vitamins plays an important role in maintaining health and physical activity. You may have heard that B-vitamin supplements improve energy levels. This is because many of the functions of vitamin B are related to food metabolism.

Optimal levels of B vitamins can help the body better absorb and use the nutrients from the food you eat. This article will let you know about the benefits of vitamin B complex, as well as food sources and potential signs of deficiency.

From this article you will learn:

  • what is vitamin b complex
  • vitamin B complex deficiency symptoms
  • who should take the complex
  • Benefits of B Complex Vitamins
  • dosage of B complex

What is a vitamin B complex?

Vitamin B complex is a term used to refer to a group of B vitamins that our body needs to maintain optimal health. Because they are water-soluble and not fat-soluble, they do not accumulate in the body and must be obtained daily from the diet or supplements. B vitamins have a positive effect on appetite, vision, skin, nervous system, and red blood cell formation.

Vitamin B complex includes:

B1 (thiamine) – essential for cell growth, development and function.

B2 (riboflavin) – plays a key role in the use of food for energy.

B3 (niacin) – Plays a role in converting food into energy and aids digestion, skin and nerve function.

B5 (pantothenic acid) – helps convert food into energy; is critical for the production and breakdown of fats.

B6 (pyridoxine) – used for many metabolic functions, immunity and plays a role in brain development.

B7 (biotin) – plays an important role in the metabolism of all three macronutrients (proteins, carbohydrates and fats).

B9 (folate) – is critical for cell division and DNA formation, making it especially important in the diet of pregnant women.

B12 (cobalamin) – similar in function to other B vitamins (red blood cell development, neurological function, DNA formation), but only found naturally in animal sources.

It is worth noting that some B complex vitamin supplements also contain vitamin C, since it is also water soluble.

Food sources of vitamin B complex

B vitamins are present in many animal protein sources such as meat, fish, eggs, milk, and pork. Plant-based sources of B vitamins include leafy greens, beans, whole grains, and nuts.

Because B vitamins are so important to health, they are added to many foods. Foods such as breakfast cereal and bread (because they are so widely consumed) are usually fortified with B vitamins.

Vitamin B deficiency symptoms

When you don’t get enough B vitamins from your diet, a deficiency can manifest itself in a variety of ways. The most common is anemia, when you have low levels of B12 and/or B6 and your blood cannot carry enough oxygen around your body. Anemia can occur in those on a vegan diet, as animal products are a rich source of B vitamins.

Symptoms of anemia include headaches, fatigue, weakness, colds, or dizziness. While there are many causes of anemia, low levels of B6 and B12 can contribute to chronic anemia.

Other common symptoms of vitamin B deficiency appear on the skin, nails and hair, such as rashes or cracked skin. Prolonged thiamine deficiency causes beriberi (tingling/numbness, loss of muscle mass). Chronically low levels of vitamin B3 or niacin lead to a condition known as pellagra, which causes digestive and cognitive problems. Folate affects the production of cells and protein, so its deficiency can affect the growth of adults and children.

Who Should Take Vitamin B Complex?

Although B vitamins are commonly found in food, there are several groups of people who benefit from vitamin B complex supplementation in particular.

  • For those on a low calorie diet.
  • Vegans (usually low in B12).
  • Aging and other conditions affecting food intake.
  • People with digestive disorders who may have malabsorption of food.

Your health care provider may order a simple blood test to diagnose a deficiency. As you can see, anyone who does not eat a balanced, high-calorie diet can benefit from a B-complex supplement.

Vitamin B complex properties

The benefits of taking a vitamin B complex are due to its many functions for the normal functioning of the body. In addition to preventing diseases associated with a deficiency of this group of vitamins, such complexes can help increase energy levels and increase the effectiveness of training.

Proper levels of B vitamins improve digestion and nutrient absorption, and keep hair, skin and nails healthy. Ensuring adequate levels of B vitamins can improve mood and cognitive function.

Vitamin B complex dosage and side effects

Since the B vitamins are water soluble, they do not accumulate in the body, and overdose is usually not a concern. However, you may experience side effects from very large doses of any vitamin or supplement.

For example, starting niacin (B3) can cause skin redness, and pantothenic acid (B5) can cause stomach upset.

The following list shows the amount of each B vitamin that adults need daily. Keep in mind that we get most of this amount from food, so the supplement should not contain more than these amounts:

B1 – Thiamin: 1.1-1.2 mg per day 3 mg daily (dairy free, vegans and vegetarians may need more)
B3 – Niacin: 14-16 mg per day
B5 – Pantothenic acid: 5 mg per day
B6 – Pyridoxine: 1.2-1.3 mg per day 7 mg)
B7 – Biotin: 30 mcg of biotin per day
B9 – Folic acid: adults 400 mg per day and pregnant women 600 mg, but not more than 1000 mg
B12 – Cobalamin: 2.4 mg per day

There are two points Things to watch out for: There is a set upper limit for folic acid (B9), meaning that exceeding this amount can be harmful to health. B12 is a vitamin that is usually taken alone because it is not always well absorbed from food sources.

For this reason, it is available in several different oral supplement forms as well as injections.

Many of the B-complex vitamins are found in daily diets, but deficiency can occur due to malnutrition or absorption problems. For this reason, a B complex (on its own or as part of a multivitamin) can help meet your daily needs. Because the B-complex vitamins are water soluble, they do not accumulate in our bodies and must be taken daily.

B Complex MF, non-methyl B complex, 100 capsules

B Complex MF, non-methyl B complex, 100 capsules – Tabletka-de

B Complex MF

Have you experienced Have you ever had side effects from taking B vitamins? For example, nervousness, headaches or unpleasant arousal? This may be due to methylated nutrients!

B Complex MF is a powerful B complex containing 8 essential B vitamins, including unmethylated B12 and folinic acid.

B Complex MF is a great option if you’re looking for a once-daily B-Complex supplement that’s free of methyl donors.

This gluten-free formula is free of GMO markers. It provides over 100% of the Daily Value of all eight essential B vitamins. Powerful amounts are ideal for those who are deficient or need more B vitamins. This can greatly increase your daily multivitamin intake.

B Complex MF promotes health: Energy production hormonal balance Positive mood Nerves and brain red blood cells homocysteine ​​levels Immune system function Some people experience nervousness, headaches or heart palpitations when taking methylcobalamin and methylfolate. However, these active forms of vitamin B12 and folic acid are essential for methylation, homocysteine ​​processing, and overall well-being. (I wonder if you are sensitive to methyl donors? This article will help you determine if you need a non-methyl supplement.)

B Complex MF contains folinic acid and vitamin B12 in unmethylated forms. It contains folate as folinic acid and B12 as adenosylcobalamin and hydroxocobalamin. These methyl-free forms go through several additional enzymatic steps before becoming methyl donors. Folinic acid (folate) is readily converted in the body to methylfolate (5-MTHF). Similarly, the “adeno” and “hydroxo” forms of vitamin B12 can easily be converted to the active form of methylcobalamin. This slower delivery may provide comfort for those who are sensitive to methylated nutrients.† MF Complex does not contain: Methylated B vitamins Methylcobalamin Methylfolate S-adenosylmethionine (SAMe) Cholines Inositol Trimethylglycine (TMG or Betaine) You should never feel sick agitated, restless or nervous after taking the supplement. With B Complex MF, you can get your daily dose of B hassle-free!

Take 1 capsule daily with food, or as directed by a healthcare practitioner. Do not take within 5 hours of bedtime as it may interfere with sleep. Warnings Children and pregnant or lactating women should consult their healthcare professional before use. Do not use if the tamper is damaged.