Asda Pharmacy Won't Sell finasteride If You're Using Nizoral Wtf???!!!

[Funkymonk1]

As those from the UK will probably know ther's a supermarket called ASDA that's recently started selling Finasteride at a reasonable price. So I booked an appointment and one of the questions the pharmacist asked me was "are you using any anti fungal creams or shampoos?" When I told him I used Nizoral shampoo he said they couldn't sell me the finasteride! I was dumbstruck and told him that as far as I know ther's no interactions between the two and as we all know it's one of the "big three" and even recommended in studies to use in conjunction with finasteride to get the best results. He just said because the computer said he's not allowed to sell it ther's nothing he can do!
I've honestly never heard this before. Is there something I'm missing here? Is there some danger or interaction between the finasteride and keto based shampoos that I've missed or are Asda mis-informed?