Can a pharmacist change a repeat tablet prescription to a liquid form, as a one off?

[MathsFail]

I'm having an operation done privately and need my antidepressants to be liquid form for 4 weeks

Do I have to ask my Dr or can they do it at the chemist?

Doctor.

Doctor

In my experience the pharmacy can only prescribe exactly what's on the prescription. So if it's tablets it's tablets.
Best to go through the GP.

Doctor. Mine prescribed capsules rather than tabkets and despite knowing I am not able to have capsules and the chemist couldn't give me the tablets instead, I had to get a new script.

My Dad urgently needed 100mg of something in tablet form. They didn't have 100mg at Boots but that's what the script said. They did 50mg ones but they couldn't give him 2 lots of those.