Think that all supplements are created equal? Think again! When it comes to optimising your health, not all vitamins and supplements are up to the task. Today, we’re pulling back the curtain on the drastic difference between over-the-counter (OTC) supplements and practitioner-only prescription supplements. Practitioner-only products are listed or registered on the Australian Register of Therapeutic Goods and supplied exclusively to healthcare professionals. Practitioner-only products can only be dispensed by a healthcare professional in accordance to the law.

They usually have more scientific evidence, with ingredients of higher quality and manufacturing standards. Ingredients chosen often have higher bioavailability (absorption), and, for these reasons, their efficacy may be superior than off the shelf or OTC supplements.

Are Your OTC Supplements Just Expensive Urine?

You walk into your local health store or chemist, and you’re greeted by aisles of shiny supplement bottles promising miracles. You pick a few and go home, hopeful. Weeks later, you’re still not feeling any different—what went wrong?

Two words: Bioavailability and Therapeutic Dose.

  • Bioavailability: This is the extent to which a nutrient can be absorbed and used by your body. OTC supplements often contain fillers, binders, or low-quality ingredients, reducing their bioavailability. Practitioner-only supplements, however, are formulated to maximise absorption.
  • Therapeutic Dose: This is the amount of a supplement that produces the desired effect. Many OTC supplements contain amounts that fall far short of the therapeutic dose you actually need. Practitioner-only supplements are designed to provide doses based on clinical studies and evidence.

The fundamental values in which practitioner-only products abide to, include:


The therapeutic efficacy of a product is determined by a number of factors. The most important being the choice (& quality) of ingredients & the forms of nutrient(s) that are used within the formula. The combination of ingredients is also just as important, some ingredients work better together than on their own, this is known as synergy. An evidence-based example of this is to include Vitamin C to Iron supplements to enhance its absorption.

With regards to ingredients, often OTC products contain inexpensive & poorly bioavailable forms of nutrients or incorrect/less active components of a herb making them less superior with perhaps little benefit.

Low-cost OTC products may also contain high amounts of unnecessary excipients to help bind, stabilise or bulk out the product. Some of these excipients used, especially in very cheap products, can actually reduce the bioavailability of the active ingredients thereby further reducing their effect on the body. Low-cost OTC products may also contain allergenic ingredients such as wheat, gluten, dairy, soy and artificial colours/flavourings etc.


When it comes to products that contain herbal medicines, the quality of raw ingredients used can vary widely between OTC & practitioner-only products. practitioner-only brands utilise vigorous batch testing to ensure that the herbs that are used are:

  1. not adulterated, and;
  2. contain the correct potency of active constituents.

The process of batch testing each raw ingredient can be fairly costly for companies, therefore to keep costs down, this process isn’t often done to the same extent with OTC herbal products. Adulteration is a common problem when purchasing herbal supplements & raw herbal ingredients internationally. Supplement manufacturers receive raw herbal ingredients, often from overseas suppliers/growers, to manufacture their products. It’s not unusual for the herb that is received to be of a different species (or different herb altogether).

In summary, why choose practitioner-only supplements?

  1. Expert Guidance: Practitioner-only supplements come with the invaluable advantage of healthcare provider oversight. These experts can interpret your test results and recommend supplements that are actually effective.
  2. Quality: These supplements undergo rigorous testing and quality control, ensuring you get what you pay for—pure, potent, and effective nutrients.
  3. Personalisation: Your healthcare provider can adjust your supplement regimen over time based on follow-up tests, ensuring ongoing effectiveness.

Final Verdict: Don’t Gamble With Your Health!

OTC supplements might look appealing with their attractive labels and cheaper prices, but when it comes to your health, don’t settle for mediocrity. Choose practitioner-only supplements that are customised to your unique body chemistry. You owe it to yourself to unlock the secret code to your optimal health, and now you know just how to do it!

Consult a healthcare provider to see if you would benefit from supplement support: