How Long Does Chemotherapy Stay in Your Body?

Chemotherapy agents are powerful drugs that are used to treat cancer throughout the body. Chemotherapy drugs work by a variety of different mechanisms, but their general effect is to slow or stop the growth of cancer cells, which divide and proliferate quickly. Chemotherapy is administrated with the intention of eliminating cancer cells so that the infected body can survive and remain in remission.  

Patients may receive a number of different types of chemotherapy, depending on a variety of factors such as the stage of the cancer and the ultimate goal of treatment.  

How long chemo stays in the bloodstream 

The benefits of chemotherapy can be long-lasting. This is crucial in fighting cancer, but it raises the question of how long these drugs stay in the bloodstream. 

In fact, most chemotherapy drugs remain in the body for only a few hours or days. They’re broken down by the kidneys and liver and excreted in the urine, stool, or sweat. 

A variety of factors can influence how long it takes for the drugs to leave your body. These can include the type of chemotherapy you’ve received, the presence of other medicines in your system, your age, and how well your liver and kidneys are working. Damage to an organ can slow down the process of drug removal. 

Chemotherapy pills.
Chemotherapy pills.

Remember that even though chemotherapy is rapidly metabolized and eliminated from the body, the effects — and side effects — of the drugs can last a long time, depending on the type of chemotherapy involved. Those side effects normally include

  • Fatigue
  • Hair loss
  • Easy bruising and bleeding
  • Infection
  • Anemia (low red blood cell counts)
  • Nausea and vomiting
  • Appetite changes
  • Constipation
  • Diarrhea
  • Mouth, tongue, and throat problems such as sores and pain with swallowing
  • Nerve and muscle problems such as numbness, tingling, and pain
  • Skin and nail changes such as dry skin and color change
  • Urine and bladder changes and kidney problems
  • Weight changes
  • Chemo brain, which can affect concentration and focus
  • Mood changes
  • Changes in libido and sexual function
  • Fertility problems

Your doctor can give you a range of how long any side effects are likely to last. 

‘Detoxing’ from chemo 

Detoxing refers to the process of remoxing “toxins” from the body, either naturally or via diets or supplements, which can be unsafe and falsely advertised. A 2015 review concluded that there was no compelling research to support the use of “detox” diets for weight management or eliminating toxins from the body, according to the National Center for Complementary and Integrative Health.

Doctors and scientists say that the body already has specific systems in place (gut, liver, kidneys, and skin, to name a few) to efficiently clear toxins and waste. Eating healthy foods (such as vegetables) and drinking a lot of water helps the body break down and remove them.

Contact your doctor and/or licensed nutritionists, dietitians, and physicians to develop health-promoting strategies during and after treatment.