Any prescription medication that is sold through a licensed pharmacy in Australia has to be cleared by the Australian Therapeutic Goods Administration (TGA). The TGA inspects all of the factories that make the prescription medication and issue a Good Manufacturing Practices (GMP) license. Then each batch that is manufactured has to have a Clinical Assay conducted to ensure that the medication has been manufactured correctly. This is to ensure that you are receiving exactly what has been prescribed to you.

Buying on-line is an absolute minefield, with many sites looking like an Australian company. How do you navigate through this? When you dig further you will find that they will have URL which is not pointing to a .com.au website. If this is the case then do not purchase from them. The second tell-tale sign is that you won’t need a prescription to purchase the medication. Finasteride is only listed as a prescription medication so you will know that this is a fake site as well. Lastly, they will hide their physical address and phone numbers or they are not Australian phone numbers.

The dangers involved with purchasing on-line from one of these websites is of massive concern. The counterfeit market in pharmaceuticals is so sophisticated that the products look like the real thing. But what does it really contain. The vast number of times the counterfeit medication will contain no active ingredients, just binders and fillers. At least it won’t hurt you. In rarer cases they will contain heavy metals, boric acid, paint, and other pharmaceuticals.

The World Health Organisation estimates that when an online website hides its actual address then around 50% of the products they sell will be counterfeit.
http://www.interpol.int/Crime-areas/Pharmaceutical-crime/The-dangers