Immunologist Serum

Step 1 of the Rationale Essential Six system. IMMUNOLOGIST promises skin clarity and calmness by boosting the skin’s immune responses and intercellular communication.


Product Description

IMMUNOLOGIST SERUM promises skin clarity and calmness. Vitamin B3 and Acetyl Glutamyl Heptapetide-1 boost the skin’s immune responses by enhancing Langerhans Cell antigen presentation and endogenous anti-inflammatory functions. This powerful combination also helps normalise melanin production and targets existing pigmentation. Australian PhotoProtective and Repair Botanicals provide unique solar defensive and rejuvenation potential. Adenosine Triphosphate and Amino Acids provide a vital source of cellular energy, optimising intercellular communication and skin barrier function.



-  Restores skin clarity and calmness
-  Helps protect and enhance skin immune functions
-  Boosts skin immune responses
-  Improves signs of sun damage, including wrinkles and dryness/roughness
-  Ideal as maintenance treatment for hyperpigmentation
-  Helps regulate sebum production
-  Reduces sensitivity / anti-irritant


-  Smooth 1-2 drops of IMMUNOLOGIST SERUM over face, neck, chest and backs of hands each morning.
-  Follow with 1-2 drops of SUPER ANTIOXIDANT SERUM.
-  Finish with PHOTODYNAMIC DAY CREAM SPF15 for maximum rejuvenation and protection. 

Active Ingredients

Niacinamide - Vitamin B3
-  Boosts skin immunity by enhancing Langerhans Cell function
-  Helps fade hyperpigmentation by inhibiting melanosome transfer through dendrites
-  Assists the down-regulation of sebum production

Australian Botanical Polyphenols
- Active constituents of native Australian flora
- Epigallocatechin and Flavan - 3 Ol Catechin prevent UV-induced DNA damage.
- High potency antioxidants, providing powerful free radical defence and enhanced solar protection
- Stimulate healthy collagen production while reducing oxidative damage within skin
- Anti-inflammatory
- Strengthens capillaries and barrier function

Acetyl Glutamyl Heptapetide-1
- Immune peptide that enhances antigen binding to Langerhans Cell

Adenosine Triphosphate
- ATP provides energy source for Langerhans Cells

Ascorbyl Glucoside
- Stable Vitamin C analogue.
- Skin lightening and antioxidant properties - prevents oxidation of Langerhans cell membranes

Phytoceutical Extracts
- Antioxidant: Juniper, Orange, Neroli, Grapefruit and Lemon
- Anti-Inflammatory: Clove, May Chang (Chinese Herb used as alternative to steroids), Lavender, Lavandin and Geranium

Australian Photoprotective + Repair Botanical Extracts
- Hydrophilic: Illawarra Flame Tree, Crown of Gold, Mountain Pepper Berry, Rosella, Waratah, Banksia, Native Snowflower, Davidson Plum, Kakadu Plum and Finger Lime Caviar
- Lipophilic: Black Cypress, Blue Cypress, Native Sandalwood and Native Peach


"Rationale is the first cosmeceutical range I've tried, and in particular the Immunologist has worked really well on pigmentation and has my skin feeling soft and smooth and not so dry. The entire Essential Six range has worked so well for me that I've stopped using primer, foundation and even tinted moisturisers!! Love". - Kerrie (QLD)

"I am in love with the serum. It makes my skin feel like I have just had a facial everyday. It helps a lot with fading old acne scarring and also preventing scarring in the first place." - Missy (VIC)

“ I am not really a fan of cosmetic procedures or medication, but agreed because I was at a complete loss and desperate for a skin solution. I was given a sample of the Immunologist serum to try. And guess what? The redness reduced and the bumps went away. My skin looks the best it has looked in eighteen months.  No antibiotics, and no laser. So it's really just a thank you. In only three weeks, Rationale products made a huge difference when nothing else worked. I hope more rosacea sufferers know about your products.” - Elise (WA)

“This little Niacinamide miracle worker is solely responsible for ridding my complexion of pigmentation post 2 kids!! I’ve never seen anything like it.”- Samantha (NSW)

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As your order is to be delivered outside of Austraila, it may incur local customs duty, import taxes and/or fees determined by the destination country. The recipient of the shipment is responsible for all duties taxes and fees. If you refuse a shipment, you are responsible for the original shipping charges and any fees that are incurred on the package.