Overview

Benfotiamine, a form of vitamin B1 that is made in a lab, is used to increase vitamin B1 levels. It is available over the counter as a dietary supplement. Benfotiamine is usually well tolerated, although there is not enough research to know what the common side effects may be. Before taking benfotiamine, tell your health care provider about all of your health conditions and any medicines or supplements you may be using.

Uses

What is benfotiamine used for?

Benfotiamine is commonly used for the following reasons.

• Low vitamin B1 levels from various causes, including vitamin B1 deficiency (beriberi)
• Nerve problems from diabetes or alcohol (neuropathy)
• Dementia, including Alzheimer’s disease

Note: The FDA has not reviewed benfotiamine for safety and effectiveness. Learn more about dietary supplements here.

How does benfotiamine work (mechanism of action)?

Benfotiamine is a form of vitamin B1. Your body uses vitamin B1 to produce energy and help your cells to grow and function properly.

The natural form of vitamin B1, called thiamine, is found in foods. Benfotiamine is synthetic, which means that it is made in a lab. Studies show that your body absorbs benfotiamine better than thiamine, which can help to increase your vitamin B1 levels faster. However, because benfotiamine is made in a lab and has not been studied as much as thiamine, it is not clear if it has all of the same risks and benefits as thiamine.

In the United States, most people get enough vitamin B1 from their diet. It is found in grains, fish, meat, black beans, soybeans, seeds, and nuts. It is also found in many fortified cereals and breads. For most adults, the recommended daily intake of vitamin B1 is 1.1 to 1.2 milligrams (mg). However, some people either do not get enough from their diet or have trouble absorbing it. When this happens, you can take benfotiamine to replace what you are not getting from your diet.

In people with diabetes or alcohol use disorder, harmful substances can build up in the nerve cells over time. Benfotiamine may help reduce the amount of these harmful substances. Some people with diabetes or alcohol use disorder also have low vitamin B1 levels. As a result, taking benfotiamine may help reduce some symptoms of nerve problems caused by diabetes or alcohol.

Benfotiamine is also sometimes used for dementia and Alzheimer’s disease. But it is not clear if or how benfotiamine may work for this use.

How should I store benfotiamine?

You should store benfotiamine according to the product label. Most dietary supplements should be kept in a cool, dry location that is out of the reach of children and pets and not in direct sunlight.

Side Effects

What are the most common side effects of benfotiamine?

Benfotiamine is usually well tolerated. But there is not enough research to know what the common side effects may be. Tell your health care provider if you have any side effects that bother you.

There may be side effects of benfotiamine that are not listed here. Contact your health care provider if you think you are having a side effect of a supplement. In the U.S., you can report side effects to the FDA at www.safetyreporting.hhs.gov or by calling 888-SAFEFOOD (888-723-3366). In Canada, you can report side effects to Health Canada at www.health.gc.ca/medeffect or by calling 866-234-2345.

What are the serious side effects of benfotiamine?

While less common, the most serious side effects of benfotiamine are described below, along with what to do if they happen.

Severe Allergic Reactions. Benfotiamine may cause allergic reactions, which can be serious. Stop taking benfotiamine and get help right away if you have any of the following symptoms of a serious allergic reaction.

• Breathing problems or wheezing
• Racing heart
• Fever or general ill feeling
• Swollen lymph nodes
• Swelling of the face, lips, mouth, tongue, or throat
• Trouble swallowing or throat tightness
• Itching or skin rash
• Bumps on the skin called hives that can be red, pink, white, or brown depending on your skin tone
• Nausea or vomiting
• Dizziness, feeling lightheaded, or fainting
• Stomach cramps
• Joint pain

Precautions

Who should not use benfotiamine?

Allergies to Ingredients. People who are allergic to any of the following should not take benfotiamine.

• Benfotiamine
• Thiamin
• Thiamine
• Vitamin B1
• Any of the ingredients in the specific product

Your pharmacist can tell you all of the ingredients in the specific benfotiamine products they stock.

What should I know about benfotiamine before using it?

Benfotiamine is a dietary supplement. It cannot be marketed to treat or cure a disease.

Read and follow the directions on the specific product you are taking, or take it as recommended by your health care provider.

Keep benfotiamine out of the reach of children.

The FDA has not tested benfotiamine products to confirm that they contain the ingredients stated on their labels. Some dietary supplements have been tested by third-party organizations to confirm that they contain the ingredients listed on their labels and do not contain any harmful chemicals. Learn more about how to choose a safe dietary supplement product here.

What should I tell my health care provider before using benfotiamine?

Tell your health care provider about all of your health conditions and any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. This will help them know whether benfotiamine is right for you.

In particular, make sure that you discuss any of the following.

Current and Past Health Conditions. Tell your health care provider if you have or have had any of the following.

• Diabetes
• HIV
• Drink large amounts of alcohol
• Weight loss surgery
• Heart failure

Other Medicines and Supplements. Benfotiamine may interact with other medicines and supplements. Before taking benfotiamine, tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using. See the Interactions section for more details.

Pregnancy. It is not known if or how benfotiamine could affect pregnancy or harm an unborn baby. Tell your health care provider if you are pregnant or plan to become pregnant.

Breastfeeding.Benfotiamine passes into breast milk. Tell your health care provider if you are breastfeeding or plan to breastfeed.

Interactions

Does benfotiamine interact with foods or drinks?

There are no known interactions between benfotiamine and foods or drinks.

It is unknown if drinking alcohol will affect benfotiamine, but drinking large amounts of alcohol may lower the levels of vitamin B1 in your body. It is best to limit the amount of alcohol you drink.

Does benfotiamine interact with medicines (drug interactions)?

Always tell your health care provider about any prescription or over-the-counter (OTC) medicines, vitamins/minerals, herbal products, and other supplements you are using.

In particular, make sure that you discuss if you are using any of the following before taking benfotiamine.

• Fluorouracil (5-FU), which is a type of chemotherapy used to treat cancer
• Furosemide (Lasix), which is a type of diuretic, also called a water pill

The interactions between benfotiamine and medicines are not fully understood. As with most dietary supplements, the research on drug interactions with benfotiamine is incomplete. Always check with your health care provider before taking benfotiamine with any medicines.

Dosing

What should I do if I accidentally use too much benfotiamine?

If you or someone else has used too much benfotiamine, get medical help right away, call 911, or contact a Poison Control center at 800-222-1222.

Benfotiamine is available over the counter as a dietary supplement in a wide range of doses. Read the product label closely and speak with a health care provider about how to take benfotiamine safely. Do not take double or extra doses, even if you miss a dose.