Friday, June 8, 2012

Question time for our Pharmacist Ms Uyen Dinh on Generic Medications and their "pitfalls".

Generics (non branded) are common these days and can be a safe and cheaper alternative to the "original medication" (branded).  However, there are some pitfalls which one needs to be aware.
  1. Generic medications are not always identical to their branded versions.  Yes, they contain the same amount of the active drug, however, they may vary markedly in the other components which make up the medication (what we call excipients).  These other components are fillers and binders etc which make up the medication, hence, generic medications will vary in shape, colour and tablet/capsule size.  This variation may give rise to allergies to adverse reactions to individuals who may not tolerate certain ingredients. 
  2. Accidental over-medicating is a very common and serious side-effect of generic medication.  All generic medications differ in packaging and labelling from their branded versions, and most generic medications differ in tablet / capsule shape and size (the only exceptions are those generics produced by the same manufacturer as their branded versions, in which they usually only repackage the box and labelling).  This causes a lot of confusion with those patients who take several different types of medications, as well as the elderly.  It is not uncommon for patients to be taking 2 or 3 generic brands of the SAME medication at the SAME time, and only discovering this to be the case when they are queried by their pharmacist or doctor, or when they develop symptoms of overdosing, or worse.  This issue used to predominantly affect the elderly and those on multiple medications, but now with the market being flooded with generics, these alternative brands can affect everyone.  Even those who only take the occasional course of antibiotic - the medication looks different, but is it actually a different type of drug to the medication taken previously which caused a severe allergy?
  3. Generic medications contain the same active drug and dosage as their branded version, but they may not produce an identical clinical / therapeutic effect.  The FDA and TGA and other government bodies regulating medicines allow for a certain "window" of clinical equivalence (what we term bio-equivalence).  If the drug company can show that their generic version falls in this "bio-equivalent window" then they are approved to be a generic version.  As this "window" indicates a range rather than a single figure, this means that the generic may not produce the exact same therapeutic effects.  This is a problem with patients who take long term medications where their doctor has made dosage adjustments (termed "dosage titration") over the period of time to give the patient the most beneficial and appropriate therapeutic effect from their medications.  An example is an individual with Bipolar who has been titrated on "Epilim" for mood control, who may destabilise when changed to a generic version.
Ms Uyen Dinh
B. Pharmacy University of Qld
Priority Health Medical Centre

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