Side Effects of the First Session of Chemotherapy

Chemotherapy is a powerful drug regimen that is used to kill cells that replicate rapidly. The chemotherapy process is physically demanding, and many patients notice side effects after a single treatment. There are a variety of different drugs used for chemotherapy. Depending on the choice of chemotherapy medication, the doctor may be able to predict the likelihood of the patient developing different side effects.

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Fatigue, nausea, vomiting, loss of appetite, diarrhea and fever are all common side effects that may occur after the first session of chemotherapy. Some people experience these symptoms immediately after their first session, while others may develop some or all of these side effects within hours of the completion of their first chemotherapy session. Other early chemotherapy side effects include mouth sores, pain and hair loss, but these side effects typically develop in the weeks after treatment begins.

Time Frame

It is difficult to determine the exact time frame for developing side effects of chemotherapy. The most well-known side effect, hair loss, does not normally start until 2 weeks after the first chemotherapy session. However, many people don't make it out of their first chemotherapy session without experiencing profound nausea and even vomiting or diarrhea. Fatigue typically develops soon after the end of the first chemotherapy session and may last a day or so after each treatment or plague the patient throughout the course of treatment.


One side effect of chemotherapy that few people are able to escape is fatigue. Chemotherapy is typically given as an outpatient service, and many people mistakenly believe that because they are returning home the same day, they don't need to take any special considerations for their health. Having some help arranged at home can greatly reduce the fatigue levels of the chemotherapy patient. Someone to prepare proper meals and help with household chores will allow the patient to recover better between chemotherapy sessions.


Often people believe that their hair will immediately fall out after their first chemotherapy session. Hair loss typically begins in the first month of treatment, but not immediately. The hair loss is also gradual. Losing your hair can be an emotional process, but the fact that it occurs gradually, over a period of weeks, may allow the patient time to come to terms with the process. Side effects that cancer patients should prepare for early in the treatment process are various digestive issues, including nausea and loss of appetite, and overwhelming fatigue. Preparing for these allows the patient to keep her strength up for the rigors of treatment.


While there is no way to prevent side effects from chemotherapy, there are ways to manage them. By carefully monitoring how they feel, patients can work with their doctors to develop a plan for controlling fatigue, nausea and other digestive issues. After the initial chemotherapy session, the oncologist may provide medications that will lessen the effects of certain side effects or wait until the patient develops specific complaints before offering treatment.