1) OTC (Over The Counter) are drugs that are less potent and relatively safe, which you can get without a pharmacist. The second category is those drugs that can be dispensed by a pharmacist. The 3rd category is those drug that need a doctor's prescriptions.

2) Miconazole or ketoconazole, etc, are anti-fungal drugs. There are several brands which are OTC with different prices. Check the ingredients on the lable to make sure antifungal components exist.

3) Guardians are chain-pharmacies in Singapore. There are tons of them. Ask the pharmacists inside the counter for more instructions on how to use the drug.