I currently work behind the counter at Boots as a Healthcare Advisor, so if you have any questions about what's available on the shelf vs. behind the counter vs. on prescription, just ask (or PM)

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But to answer your question: yes, you go up to the pharmacy counter and just ask for what you want - you don't have to talk to the pharmacist unless you want to as all the advisors are trained (they will have taken or will be working towards healthcare exams and are qualified to assist you) and know to be discreet if you have an embarrassing problem. The advisor will ask you questions like: what are your symptoms?, how long have you had them?, have you used the medication before?, are you taking any other medicines? etc. to determine if the product is suitable for you to use (some people cannot take certain products due to existing conditions or interferences with other medications, but the customer may not always know this).
Diflucan is available behind the counter - you don't need a prescription for it - and you can buy it as long as you have been diagnosed by the doctor in the past and have used it (or other similar treatments such as the cream) before. However, you can only treat yourself up to twice within a 6-month period and we advise that if you need it more often that you visit the doctor in case there is an underlying cause that needs to be sorted out.
In Boots, we don't actually stock the Diflucan brand tablet anymore (we used to), but we sell a Canesten one and a Boots-own brand one instead. It costs £10.50 for the Boots one, £11.50 for the Canesten one and £12.99 for the Canesten tablet plus cream combination pack - so in fact, it is cheaper on prescription!
Hope this helps

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