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Rationale

RATIONALE #5 The Serum

Regular price
$194.00
Regular price
Sale price
$194.00
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Rationale’s #5 The Serum is an advanced formula designed to recalibrate the skin’s pH balance, refine texture, and even skin tone. By combining a complex of Hydroxy Acids, it boosts radiance while reducing the appearance of fine lines and uneven pigmentation. Perfect for those seeking smooth, luminous skin, this serum enhances overall clarity and firmness.

 

My Benefits
  • Refines skin texture for a smoother appearance
  • Evens out skin tone and reduces pigmentation
  • Boosts radiance and enhances brightness
  • Gently exfoliates, revealing fresh skin
  • Helps firm and strengthen the skin
skin Suitability
  • Suitable for all skin types
  • Ideal for those with uneven skin tone and texture concerns
How to use me

Shake the bottle gently before use. Dispense 2–3 drops into your palm and smooth over the face, neck, décolletage, and backs of hands. Avoid the delicate eye area. Use in the morning as part of your AM skincare routine

My Key Ingredients
  • Salicylic Acid: Exfoliates the skin by unclogging pores, improving texture, and reducing inflammation.
  • Lactic Acid: A gentle exfoliant that also hydrates and smooths the skin.
  • Saccharum Officinarum (Sugar Cane) Extract: A natural exfoliant and humectant that helps retain moisture while enhancing cell renewal.
  • Tea Tree Leaf Extract: Provides antimicrobial benefits, calming irritated skin.

Sandalwood Seed Oil: Nourishes and soothes the skin, helping to improve overall

All of My Ingredients

Aqua (Water), Ethoxydiglycol, Vaccinium Myrtillus Fruit Extract, Dimethyl Isosorbide, Salicylic Acid, Lactic Acid, Saccharum Officinarum (Sugar Cane) Extract, Glycerin, Citrus Aurantium Dulcis (Orange) Fruit Extract, Citrus Limon (Lemon) Fruit Extract, Sodium Levulinate, Acer Saccharum (Sugar Maple) Extract, Diutan Gum, Melaleuca Alternifolia (Tea Tree) Leaf, Sodium Anisate, Mentha Australis Leaf Extract, Butylene Glycol, Santalum Spicatum (Sandalwood) Seed Oil, Magnesium Aspartate, Zinc Gluconate, Sodium Benzoate, Citric Acid, Copper Gluconate, Glycine, Serine, and more​

    5-SERUM+InHand
    5-SERUM+Primary
    5-SERUM+Swatch

    The 'YOU' Guarantee

    • Quality

      Medical-grade, science-backed skincare solutions.

    • Doctor-Led

      Expert care from trusted professionals.

    • Fast Shipping

      Fast, reliable delivery to your doorstep.

    • Support

      Friendly, dedicated customer care team.

    Identifying Your Skin Concerns

    Hyperpigmentation

    Hyperpigmentation is characterised by brown patches that are darker in colour than the surrounding skin. It is most commonly seen as freckles, age spots, and post-inflammatory hyperpigmentation. It is characterised by:

    • Uneven skin tone
    • Dark spots after a break-out
    • Symmetrical dark brown patches on top lip, orbital bone, and forehead

    The Recommendation

    Skin experiencing Hyperpigmentation needs Antioxidants and brightening actives to visibly even tone, in addition to SPF to protect against further damage. This skincare Ritual features ingredients that brighten the complexion’s appearance, support healthy cell renewal, and protect against solar damage—for a more even-looking complexion.

    Fine Lines and Wrinkles

    The Definition

    Fine lines and wrinkles refer to the loss of collagen and elastin, which occur as a result of ageing and sun exposure. Fine lines and wrinkles are characterised by:

    • Facial sagging
    • Fine lines on the forehead
    • Cross-hatching lines around mouth and eyes

    The Recommendation 

    Skin experiencing fine lines and wrinkles needs Vitamins and firming actives to support the skin’s architecture and to preserve collagen, as well as SPF to protect against solar-induced damage. This skincare Ritual features ingredients that visibly improve skin firmness, support collagen, and maintain skin’s innate repair capacity for a firmer, more defined appearing profile

    Sensitivity

    The Definition

    Sensitivity often presents as red, irritated skin, which is highly reactive to heat, active ingredients and the sun. Sensitivity is characterised by:

    • Skin that appears red and irritated
    • Low tolerance to active ingredients
    • Skin that flushes easily

    The Recommendation 

    Skin experiencing sensitivity requires calming and nourishing actives to support healthy barrier function and soothes the skin. This skincare Ritual features ingredients that reduce the appearance of redness and support healthy barrier function for a calmer, clearer complexion.

    Congestion and Oily

    The Definition

    Congestion can occur when pores become clogged, or as a result of producing excessive sebum. It is characterised by:

    • Raised bumps with a red or white head
    • Small bumps under the skin mouth and eyes
    • Red, inflamed cysts

    The Recommendation

    Skin experiencing congestion requires resurfacing actives which support healthy pH and promote cell turnover. This skincare Ritual features ingredients that refine tone and texture, while balancing sebum production and supporting a healthy skin microbiome for a clearer, more refined complexion.

    Dryness

    The Definition

    Dryness occurs when the skin is lacking crucial lipids required for healthy skin. It is characterised by:

    • Dry, scaly skin
    • Small patches of flaky skin
    • Tight sensation after cleansing or showering

    The Recommendation 

    Skin experiencing dryness requires intense nourishment to protect against moisture loss and to prevent damage from environmental aggressors. This skincare Ritual features ingredients that lock in moisture and strengthen the skin’s barrier to alleviate dry, flaky skin for a smoother complexion.

    Dehydration

    The Definition

    Dehydration occurs when the skin is lacking water, resulting in loss of moisture. It is characterised by:

    • Very fine lines all over the skin
    • A tight sensation on the skin
    • Dull appearance

    The Recommendation

    Skin experiencing dehydration requires water-binding actives to increase moisture and prevent damage from environmental aggressors. This skincare Ritual features ingredients that amplify hydration for a more radiant complexion.

    FAQs

    Do you offer flexible payment options?

    Yes! We accept Afterpay, Zippay, TLC finance, Visa, Mastercard, and cash in-clinic for easy and secure payments.

    How can I receive my order?

    We deliver Australia-wide and internationally, plus offer free local pickup at our Forresters Beach and Newcastle locations.

    How long does shipping take?

    Standard shipping within Australia typically takes 2–5 business days, and express delivery takes 1–3 business days, depending on your delivery location​.

    What if I don't know which products I need?

    Try our online Skin Quiz! It’s a quick and easy way to discover products tailored to your skin type and concerns.