Fluorouracil (5-FU) chemotherapy is a very common form of chemo. It uses 5-FU, a chemical that travels around the body, killing cancer cells. It is useful for treating certain forms of cancer, such as gastrointestinal cancers.

However, this medication can cause side effects such as diarrhea, vomiting, and dehydration.

This article looks at one type of chemotherapy medication, 5-FU. The article will look at what 5-FU is and what it does. It will also detail some side effects of 5-FU before answering some frequently asked questions.

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Doctors use the pharmaceutical agent 5-FU for various cancer treatments. It has Food and Drug Administration (FDA) approval for this purpose.

Some research has shown that 5-FU is the third most common chemotherapy drug worldwide when it comes to treating solid cancers. These cancers contrast with liquid cancers, such as lymphoma and leukemia.

A 2021 literature review explains that doctors have successfully treated certain cancers with 5-FU. These include:

Cancer refers to when some of a person’s cells begin to grow uncontrollably. Chemotherapy is a form of treatment that uses medications to target cancer cells.

According to a 2023 review, chemotherapy works by reducing the ability of cancer cells to multiply. This inhibits the potential of tumors to spread across a person’s body.

As a 2022 review clarifies, 5-FU for cancer is a systemic treatment. This means that the 5-FU will travel all around a person’s body, affecting cancer cells when it finds them.

It may do so on its own or in combination with other pharmaceuticals. This latter is often much more effective than 5-FU chemotherapy on its own.

However, doctors do not recommend taking 5-FU chemo orally. This is because the body has difficulty absorbing much of it through the stomach and intestines.

For this reason, doctors will recommend an intravenous administration, which involves injecting the 5-FU directly into a person’s veins.

Chemotherapy drugs work by inhibiting the development of cancer cells. However, the body is a very complex system.

This makes it difficult for scientists to design drugs that only affect certain bodily structures. For this reason, side effects can occur.

This is also true with 5-FU — as the chemical travels around the body, it can also cause problems with healthy cells.

The same 2022 review details the side effects that can follow. They include diarrhea, which is the most common side effect.

Other common side effects include:

In some cases, 5-FU chemo can cause more serious problems. These include:

Doctors must closely monitor individuals whose 5-FU chemo has caused these side effects.

This section answers some frequently asked questions about 5-FU chemo.

What cancers does 5-FU treat?

Chemotherapy with 5-FU can treat various cancers. According to scientific research, several gastrointestinal cancers and some cervical cancers respond well to 5-FU chemotherapy. The same is true of head and neck cancers.

What is the success rate of 5-FU chemotherapy?

The success rate of 5-FU chemo will depend on many factors. These include the stage of someone’s cancer, what type of cancer they have, and their general state of health.

The efficacy of other forms of treatment is also relevant. Chemotherapy with 5-FU tends to be far more effective in combination with other therapies.

Cancer occurs when the body’s cells begin to grow and spread atypically. Chemotherapy suppresses the development of cancer cells, lowering the risk of tumors spreading around the body.

The chemical agent 5-FU is common in chemotherapy treatments — many chemo regimens use it. There is evidence that 5-FU chemotherapy is useful for treating gastrointestinal, cervical, and head and neck cancers. However, it is much more effective in combination with other therapies.

Although 5-FU inhibits cancer cells, it can also harm healthy ones. Chemotherapy with 5-FU therefore causes side effects, which commonly include diarrhea, nausea, and vomiting.

However, 5-FU chemo can also lead to fever, pulmonary embolisms, and various blood problems. Such side effects require careful monitoring by doctors.