How to Combat Fatigue As A Side Effect of PARP Inhibitors

While PARP inhibitors can be game-changing in ovarian cancer treatment, a common side-effect of this category of drugs is fatigue. In some cases, this fatigue — coupled with the body’s energy demands of fighting cancer itself — can be challenging for patients, says Dr. Stephanie Wethington, a gynecological oncologist at Johns Hopkins University.

How PARP Inhibitors Work

PARP inhibitors are most effective at arresting the growth of cancer when a BRCA gene mutation is present. But this new class of drugs has also been found helpful for women without the mutation, who are now approved to receive the medication. And PARP inhibitors can be given at all stages in cancer treatment. They work by preventing damaged DNA in tumor cells from repairing itself, leading to cell death.

Women who are diagnosed with ovarian cancer should have genetic testing to determine if they carry the BRCA gene mutation. This information can guide their treatment plan. It can also provide vital information for family members, who may also be at risk of having the gene and developing the cancers — both breast and ovarian — most often associated with it. PARP inhibitors can both decrease the chance of an ovarian cancer recurrence and increase life expectancies for ovarian cancer patients with or without the BRCA mutation.

Most recently, the American Society of Clinical Oncology (ASCO) released new guidelines recommending PARP inhibitors be offered to women, with or without genetic mutations, who are newly diagnosed with stage III or IV ovarian cancer and have improved with chemotherapy.

Note Energy Levels: Before and After

So how can patients tackle feelings of fatigue?  First, take note of changes in your energy levels before and after you begin a PARP inhibitor regimen. Share this information with your doctor. In some cases, a modified dose can offer relief. “Certainly if this side effect is quite severe, the patient and provider should talk about dose adjustments that they may consider,” says Dr. Wethington

The adjusted dose may be temporary, at the beginning of treatment, to allow the body to adjust and “get over the hump” of the start of the new drugs, she says. But in other cases, if a modified dose is found to be effective, patients may remain on it.

Other Causes of Fatigue

Be aware, too, that many chemotherapy drugs besides PARP inhibitors also come with fatigue as a side effect. If you’re undergoing chemotherapy, you might notice an increase in energy levels once you’ve completed that portion of treatment.

“There’s no magic pill, unfortunately, for fatigue,” says Dr. Wethington. “It’s probably [caused by] all of the chemo drugs, not just PARP inhibitors. So when you put the two together it can be quite a combination and difficult to treat,” she explains.

Re-Think Your Idea of Exercise

As anyone who’s felt energized after a brisk walk knows, “the best treatment for fatigue is the opposite of fatigue, which is exercise,” Dr. Wethington notes. “Ironically exercise and physical activity are the best thing to treat fatigue with.” Although exercise may feel like more than you can manage when facing chemo-induced fatigue, physical activity can be helpful and actually help restore the body’s reserves of energy.

Don’t be limited by the idea of traditional gym workouts. There are plenty of ways to add gentle activity to your day. Choose an activity you enjoy – even if it’s moving to music at home. Or find a family member who likes to go for walks,” Dr. Wethington suggests. Especially during the COVID-19 era, when gyms and exercise studios are closed, it’s important to get creative.

Of course, every cancer journey is different, and how you’re feeling is an important factor to consider when it comes to physical activity. If you’re concerned about adding a specific type of exercise into your routine, talk it over with a doctor who’s familiar with your specific treatment.

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