EPQ

hi, does anyone have any ideas for what I could base my EPQ on
originally I was going to take chem, psych maths for A-Levels, therfore I had EPQ ideas revolving around psychology
but now I'm most likely going to take bio, chem, maths so I'm not sure what to do it on now
is it still possible to do it related to psychology or does it have to be related to my A-Levels/degree (I'm thinking of taking pharmacology)

Your epq can be completely unrelated to your level choices if you wish so psychology would still be a suitable area for you to choose a topic from