Cancer treatment often causes some degree of fatigue. Cancer can cause fatigue as well. The pattern and intensity depend on the type and schedule of your treatment.

CANCER FATIGUE: Sometimes the cancer itself can cause fatigue, depending on the type and extent of disease. If you have curable, early-stage cancer you may only notice fatigue during treatment. If you have a more advanced cancer, you may have moderate or even severe fatigue from the cancer itself. In that case, treatment for your cancer may improve fatigue considerably.

CHEMOTHERAPY: If you’re receiving a limited course of intensive chemotherapy, you may have a few days of mild-moderate fatigue after each dose, and it’ll usually improve (but not completely resolve) before the next dose. Since you’re not recovering completely after each dose, the fatigue usually gets more noticeable the longer treatment goes on. But you should recover your energy completely within several weeks or a few months after chemotherapy is finished.

In the first phase of treatment, you may even feel worse before you start to feel better. There are no safe or effective medications that can boost your energy during treatment. But some simple things you can do to maximize your stamina include:

RADIATION: If you’re receiving a limited course of radiation treatment every day for weeks, you’ll probably notice progressive fatigue that starts a week or two into treatment, with fatigue peaking a week or two after treatment ends. You’ll probably regain your normal energy level several weeks or a few months after radiation ends.

TARGETED THERAPY: If you’re receiving ongoing treatment with lower-intensity agents (such as targeted molecular therapies or immune checkpoint inhibitors) you may have little to no fatigue. But sometimes fatigue appears later and builds steadily, so if you notice your energy level changing the longer the treatment goes on – talk to your provider.

You’re going to be operating with less energy than before, at least for a while. And you’re going to have to budget that energy accordingly. This may mean giving up certain activities or chores you no longer have the energy for.