Thinking and memory

Low levels of sex hormones can cause problems with concentration, thinking and memory.

Sex hormones and hot flushes

Some cancer treatments can lower the levels of sex hormones in the body. The sex hormones are oestrogen and progesterone in women, and testosterone in men. The cancer treatments include hormone treatments for prostate cancer.

Prostate cancer needs testosterone to grow. Hormonal treatments aim to:

  • stop the testicles from making testosterone
  • stop testosterone reaching cancer cells

How hormone therapy affects thinking and memory

Memory and the way we process information is called cognition. Cognitive ability describes how well you can remember and concentrate. This includes how you manage doing more than one task at the same time.

Some people notice changes to how they think and remember after hormone treatment for prostate cancer. It may not affect you every day. You may forget a word during a sentence or struggle to remember a shopping list.

Doctors call this ‘mild cognitive impairment’. You may hear it described as ‘chemo brain’, or a general ‘fogginess’. It doesn’t only happen after chemotherapy. It can also be a side effect of hormone treatment.

For many people the changes are very subtle and get better after treatment.

Researchers are trying to find out how hormone treatment affects memory.

Tests for changes in thinking and memory

The only tests available are those used to test dementia. They aim to see big differences in memory and thinking. Changes after cancer treatment can be very subtle. 

A team of doctors (the International Cognition and Cancer Task Force - ICCTF) is researching new tools doctors can use to test memory changes after cancer treatment. 

Tips to help with changes to thinking and memory

  • Keep a diary or calendar to help you remember what you need to do each day
  • Write lists of jobs to do, things to buy or where you keep things you use every day
  • Use post it notes to remind you to do tasks
  • Write down people names with a description to remember them
  • Repeat information back to people to check understanding
  • Keep your mind active, you could try crosswords, sudoku or puzzles


Researchers are looking into a number of treatments that may be helpful. A trial that compared patients having hormone treatment alone with those having oestrogen added to hormone treatment suggested that patients who took only hormone therapy had reduced memory and slower thought processes.

Research is also being carried out into drugs that increase the blood and oxygen supply to brain cells.

Last reviewed: 
16 Jul 2019
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    J Wefel and others
    Cancer Journal for Clinicians, 2015. Vol 65, Pages 123-138

  • Cognitive functioning in men receiving androgen deprivation therapy for prostate cancer: a systematic review and meta-analysis
    H McGinty and others
    Supportive Care in Cancer, 2014. Vol. 22, Pages 2271-2280

  • Cognitive changes associated with ADT: a review of the Literature
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    Asian Journal of Andrology, 2012. Vol 2, Pages 232-238

  • Effects of androgen deprivation on brain function in prostate cancer patients - a prospective observational cohort analysis.
    H Chao and others
    BMC Cancer, 2012

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