Chemotherapy is one of the most used treatments against cancer. It is made by drugs that mix with the bloodstream and are carried to the whole body, destroying cancer cells to stop tumors from growing. Know more.

Chemotherapy is a treatment that uses very potent drugs to eliminate cancer cells that multiply rapidly in the body and form the tumor. They mix with the bloodstream and travel to all parts of the body, destroying diseased cells and preventing them from spreading.

Several types of chemotherapy drugs are available for the treatment of different neoplasms. Chemo can be done alone or in combination with surgery, radiation and other approaches to fighting cancer.

Does chemotherapy cause pain?

The only pain that the patient should feel is that of the needle being inserted into the skin, at the moment of puncturing the vein. In some cases, certain chemotherapy drugs can cause a feeling of discomfort, stinging, burning, reddened skin patches, and itching – however, these are manageable adverse effects.

The healthcare professional responsible for administering chemotherapy should be notified if any different reactions occur.

Types of chemotherapy

Chemotherapy can be used in several different scenarios. Here they are:

  • Curative chemotherapy: in an attempt to cure the cancer completely;
  • Neoadjuvant chemotherapy: given before or associated with other treatments, to make them even more effective. Here, the aim of chemotherapy is to “shrink” the tumor to potentiate the effect of radiation therapy or surgery;
  • Adjuvant chemotherapy: given after surgery or radiation therapy, as a way to prevent the cancer from coming back; and
  • Palliative chemotherapy: if a cure is not possible, chemotherapy may be performed for the relief of cancer symptoms.

The duration of treatment is planned according to the type of tumor and the stage it is in, and is defined individually. Only the doctor will indicate the time of termination.

The choice of chemotherapy

There are several drugs available for the treatment of cancer. The oncologist evaluates each case and proposes a treatment plan, which may include just one chemotherapeutic agent or use more than one type simultaneously.

The choice of medication and the way in which the treatment will be carried out (interval between chemo sessions and total duration) depend on some factors, such as:

  • Type of cancer;
  • Tumor size;
  • Tumor location;
  • Presence or absence of metastases;
  • Patient’s age;
  • General health status (whether they are debilitated or not);
  • Evaluation of other medications in use; and
  • If the patient have had previous treatments for cancer or if they are a treatment “naïve”.

Some chemotherapeutic agents can be used in diseases other than cancer, such as lupus and rheumatoid arthritis, or in the preparation of a patient who will undergo a bone marrow transplant.


Chemotherapy can be given in different ways, and only the doctor can determine which is best for each patient.

Treatment is administered by specialist nurses and nursing assistants, either in the hospital or at specialized clinics, and can be done in the following ways

  • Oral route: the drug, in the form of tablets, capsules or liquids, is ingested by mouth. It can be taken at home;
  • Intravenous: the chemotherapy agent is given directly into the vein or through a catheter (a thin tube placed in the vein), as an injection or diluted in serum;
  • Intramuscular: the medication is applied directly to the muscle, through injections;
  • Subcutaneous: the medication is given by injection, under the skin;
  • Topical: the drug, in the form of a liquid or ointment, is applied to the region affected by cancer (skin or mucosa); and
  • Intracranial or intrathecal: although this use is less frequent, it is an option. The drug is applied to the cerebrospinal fluid (spine fluid) by the doctor himself in an appropriate room or operating room.

Possible adverse effects and complications

While chemotherapy is an effective way to treat many types of cancer, it can also come with side effects. Most of the time, they are “manageable”, that is, they can be circumvented through treatments and other approaches.

The most common reactions to chemotherapy are:

  • Weakness and fatigue;
  • Diarrhea;
  • Constipation;
  • Weight loss;
  • Weight gain;
  • Mouth sores;
  • Hair loss and other body hair (such as eyelashes and eyebrows);
  • Fever;
  • Infertility;
  • Bruises;
  • Seasickness;
  • Vomiting; and
  • Dizziness.
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