Contraindications of Vitamin B Complex

By Max. D Gray. Updated: January 25, 2017
Contraindications of Vitamin B Complex

The vitamins that make up the well-known B complex are essential for good cell activity in the body, contribute to the proper functioning of the central nervous system and are involved in red blood cell production. These vitamins can be found in many foods - such as liver, fish, meat, shellfish and dairy products. There are also vitamin supplements that provide plenty of vitamin B.

Although vitamin B is one of the best vitamins for ensuring that your body is functioning properly, overconsumption can cause side effects. This is not usually associated with the excessive consumption of foods that are rich in vitamin B complex, but rather with consuming too many vitamin B supplements. This OneHowTo article explains all about the contraindications of vitamin B complex. Interested? Then read on!

Steps to follow:

Many side effects are simply caused when people take vitamin B supplements when they are not vitamin B deficient. Everyone needs vitamin B so that their bodies can function properly, and most people can get the amount they need through foods such as seafood and meat. However, when a person starts taking vitamin B supplements without medical advice, this may cause side effects.

Vitamin B supplements should be taken by people who are deficient in this vitamin complex because, although overconsumption isn't lethal, certain negative effects may have an impact upon a person's health.

In this OneHowTo article we'll tell you which foods are rich in vitamin B.


Overconsumption of vitamin B1, B6 and B12 is not recommended for pregnant or breastfeeding women. These vitamins can also cause some drowsiness, and so are not recommended for people who handle machinery or work with heavy loads. People with kidney or liver disease are also advised against taking these three B complex vitamins.

If you don't exceed your recommended daily dose of vitamin B, as per your doctor's instructions, and you don't have any of the above-mentioned conditions, there is no contraindication in taking vitamin B. But if you do, you may begin to develop some of the following symptoms and side effects.

Contraindications of Vitamin B Complex - Step 2

When a person exceeds the maximum amount of vitamin B that the body can handle, complications set in. Although everyone can take vitamin B, overconsumption can lead to stomach upsets. Diarrhoea is one of the side effects of taking too much vitamin B, and normally presents with mild discomfort that can be mistaken for indigestion.


Another of the contraindications of vitamin B complex is that if consumed in excess it can also cause rashes to appear. These rash breakouts are usually accompanied by hives or itching.

Contraindications of Vitamin B Complex - Step 4

Difficulty breathing and heart palpitations can also result from taking too much vitamin B. Although symptoms may have disappeared by the next day and don't generally represent a major health risk, if the vitamin continues to be taken in excess, this may lead to further complications.


One of the main side effects of excess vitamin B consumption is strange psychological behaviour. The person may experience anxiety or panic attacks due to changes in the functioning of the central nervous system. However, symptoms improve when excess vitamin B is eliminated by the body.

Contraindications of Vitamin B Complex - Step 6

Large doses of vitamin B can cause early onset Leber's hereditary optic neuropathy, a hereditary disease that damages the optic nerve. Insomnia is another side effect of vitamin B overconsumption. All of the above symptoms may be more severe if the excess vitamin B was injected into the body.

This article is merely informative, oneHOWTO does not have the authority to prescribe any medical treatments or create a diagnosis. We invite you to visit your doctor if you have any type of condition or pain.

If you want to read similar articles to Contraindications of Vitamin B Complex, we recommend you visit our Drugs & supplements category.

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Excellent article. Well written and very informative.
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