Scientists Say: Relapse

This is what happens when someone’s health gets worse, after it had been getting better


People with mental illnesses such as eating disorders can relapse. They go back to harmful eating habits after they had been eating healthfully.

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Relapse (verb, noun, “REE-laps”)

This is a word that doctors and scientists use to describe an illness that gets worse after a time when the patient seemed to be getting better. For example, a bacterial infection may respond to an antibiotic prescribed to treat it. But a patient may not finish all their antibiotics. Or the bacteria may change, developing resistance to the drug. Then, the bacteria may come roaring back, making the patient sick again.

People can also relapse after cancer treatment. A tumor may respond to a drug and get smaller. But over time, the cancer cells might adapt to resist the drugs that once would have killed it.  The cancer then can again start to grow. Mental illnesses can also relapse. Someone’s depression, drug abuse, anxiety or eating disorder might respond to treatment at first. But a new life stress might make the patient relapse. 

In a sentence

People with eating disorders may recover and relapse many times, which makes the illnesses hard to treat. 

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Bethany Brookshire was a longtime staff writer at Science News Explores and is the author of the book Pests: How Humans Create Animal Villains. She has a Ph.D. in physiology and pharmacology and likes to write about neuroscience, biology, climate and more. She thinks Porgs are an invasive species.

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