Once you pay your franchise your cost will be 10%, chf 33 for a 3 month supply. Given that it is on the compendium. This is why for people with expensive meds or lots of prescriptions, it often makes sense to have a low franchise insurance.
You may need a doctor's prescription to buy medication at a pharmacy. Some pharmacies are a bit more lenient and may make an exception for tourists from abroad, especially if you ask at a pharmacy at a large, central railway station, for example.
If they do require a prescription, you could get one sent from your doctor at home, and typically a Swiss pharmacy will respect and accept that ask the pharmacy to recommend a doctor in close proximity go to a walk-in doctor's practice, such as this one in the Zurich main station https://www.permanence.ch/ (this kind of service is also available in other cities)
I'm not sure if I understood correctly, but I thought OP is from Australia, and only visiting Switzerland. Your information is, of course, correct if OP has now settled in Switzerland and arranged the obligatory Swiss medical insurance.
Oh, I missed that. Thanks! Yeah, what I wrote only applies if you are covered under Swiss insurance. Otherwise you will need a prescription from a physician. At one point, I thought there was a pharmacy in Zurich that filled scripts from abroad.