Module 6: how drugs work: learner's workbook

7.2 The placebo effect

Page last updated: 2004

The placebo effect is the well-known phenomenon in which a person takes a substance which has no pharmacological or psycho-active properties (usually a sugar pill) yet claims to experience a drug effect. This effect is based on the expectations of the person.

Doctors have sometimes used a placebo drug with some patients claiming excellent results from their placebo medication, or alternatively intolerable side effects! (Of course the patients did not realise the medication was merely a sugar pill.)

The placebo effect can have a powerful influence when people use psycho-active drugs.

Task - writing exercise

Question - Why might young people be particularly influenced by the placebo effect when they use psycho-active drugs?

Answer - (Write your answer, then check the possible answers page.)


  • The effect of a drug is determined by many factors (not just type and amount of drug)

  • Drugs can have short-term and long-term effects

  • The placebo effect can have a powerful influence when young people use psycho-active drugs.