Nocebo Effect

The nocebo effect is, in simple terms, the opposite of the placebo effect.

When negative expectations about a treatment or situation contribute to experiencing worse symptoms or side effects.

The important idea is that expectations can influence how we experience physical and psychological symptoms.

Simple example

Someone tells you:

“This food always gives people stomach problems.”

You eat it while worrying:

“I’m probably going to feel sick.”

You then notice every small stomach sensation and may genuinely begin feeling uncomfortable.

That’s an example of a possible nocebo response.

example: 2

Suppose a doctor gives two patients the same harmless pill.The doctor tells one:

“This may cause a headache.”

The person starts worrying about the headache and may actually experience one.

The pill itself didn’t contain something that causes the headache. The expectation and surrounding context may have contributed to the experience.