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Practitioner grade
Practitioner only
High-dose methylcobalamin (sublingual)
Fast acting sublingual B12 for rapid repletion
Provides 5000mcg methylcobalamin (active B12) in a sublingual tablet that dissolves under the tongue, bypassing digestive absorption entirely. Suitable for confirmed B12 deficiency and impaired intrinsic factor.
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Practitioner consult session
A 15-minute consultation. An email link will be included in your order confirmation to make the booking.
Optional 1:1 with our clinical team · $49
TGA-listed AUST L
Practitioner-grade formula
Clinician-reviewed before dispatch
Ships in 2 business days
What's in it
Each ingredient is in its most bioavailable form, at a clinically meaningful dose. No fillers, no token amounts, no marketing-led blends.
Sublingual methylcobalamin
Mecobalamin (Methylcobalamin — Vitamin B12)
The neurologically active, coenzyme form of vitamin B12. Methylcobalamin is directly bioavailable without the conversion steps required for cyanocobalamin. Sublingual delivery achieves blood levels comparable to intramuscular injection in people with impaired intestinal absorption.
5mg (5000mcg)
Always read the label and follow directions for use. Vitamins and minerals can only be of assistance if dietary intake is inadequate. If symptoms persist, consult a healthcare professional.
How to take it
Simple to take, with a few timing notes that make a real difference to absorption.
1 tablet daily dissolved under the tongue. Allow to dissolve completely before swallowing.
Dietary supplements should not replace a balanced diet. If you have confirmed pernicious anaemia or severe B12 deficiency, seek medical advice, intramuscular injection may be required initially. Vegan friendly.
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Back to Energy & Fatigue →Frequently asked.
Common questions about how OptiLabs works: testing, supplements, clinician review, returns and timing.
Why sublingual rather than oral?
Standard oral B12 requires intact intrinsic factor production in the stomach for absorption. Sublingual delivery bypasses this pathway entirely — the B12 passes directly through the oral mucosa into the bloodstream. This makes it effective even when digestive absorption is compromised.
Are the supplements safe?
All carry an AUST L designation from the TGA. Every order is reviewed by a clinician before dispatch.
Do I need a referral?
No. All tests are available to order directly. Our lab partner is NATA and RCPA accredited, operating as a direct-access pathology service.
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A proper investigation into what's driving your symptoms, with a protocol built around your results, not a generic recommendation.