Like a Canadian, I am polite to a fault.mainwarring

This is why – when a patient visits my store and they present a script for a medicine –  I always offer them the opportunity to buy the generic substitute. (if in fact one exists).

I provide this option because it saves the patient money.

A generic drug is identical-or bio-equivalent-to a brand name drug in dosage form, safety, strength, route of administration, quality, performance characteristics and intended use.

All medicines sold in Australia, whether a generic medicine or original brand, must meet the same tough quality standards set by a government agency called the Therapeutic Goods Administration (TGA). The role of the TGA is to check that all prescription medicines provide an appropriate safety and performance profile.

Generic medicines always contain the same amount and type of active ingredient as the original brand, but sometimes they can contain different fillers and colours.

Regardless of the ingredients used, all must meet the same strict standards of quality and safety.

Fillers and colours are only changed to take advantage of newer or safer ingredients or to ensure the generic medicine delivers the active ingredient in a manner equivalent to the brand medicine.

The list of TGA approved fillers and colours that can be used to manufacture any medicine is relatively small, so similar ingredients are generally used in both the generic medicines and original brands.


When a doctor insists on the supply of the original brand, he or she is only doing so at the behest of the drug company. If the TGA says the drugs have the same effect, they have the same effect. Regardless of the size of that drugs therapeutic window.

Drugs with a narrow therapeutic window

-digoxin (Lanoxin—Sigmaxin)

-amiodarone (Cordarone—Aratac)

-carbamazepine (Tegretol—Teril)

Why would the TGA list these medicines as bio-equivalent?

Good advice for and from Mr. Mainwarring

Keep calm and take your generic medicine!