Excipient Used in Herbal Formulations

Excipients are inactive ingredients added to herbal formulations to improve stability,
bioavailability, and effectiveness of the active herbal components. They ensure that the final
product is safe, effective, and patient-friendly.
Types of Excipient in Herbal Formulations

1. Binders (Adhesive Agents)
   ✔ Purpose: Helps in holding powdered herbal ingredients together in tablet and granule
   formulations.
   ✔ Commonly Used In: Tablets, Granules
   Examples:
    Gums (Acacia, Tragacanth, Guar gum, Xanthan gum)
    Gelatin
    Starch (Maize starch, Rice starch)
    Methylcellulose, Hydroxypropyl Methylcellulose (HPMC)
    Povidone (Polyvinylpyrrolidone, PVP)
   Example: Acacia gum is used in ayurvedic formulations for improving tablet integrity.
2. Diluents (Fillers)
   ✔ Purpose: Increases the bulk of the herbal formulation, ensuring uniform weight and
   accurate dosing.
   ✔ Commonly Used In: Tablets, Capsules, Powders
   Examples:
    Lactose (Common in herbal tablets)
    Mannitol (Improves mouthfeel in chewable herbal formulations)
    Microcrystalline Cellulose (MCC) (Widely used in tablet formulation)
    Calcium Phosphate
    Sorbitol, Sucrose, Glucose (Used in syrups and chewable tablets)
   Example: Lactose is used as filler in Ashwagandha and Ginseng tablets.
3. Disintegrants (Breakdown Enhancers)
   ✔ Purpose: Helps herbal tablets break down and dissolve faster in the gastrointestinal tract.
   ✔ Commonly Used In: Tablets, Capsules
   Examples:
    Sodium Starch Glycolate
    Croscarmellose Sodium
    Crospovidone
    Guar Gum, Xanthan Gum
   Example: Sodium Starch Glycolate is used in Triphala tablets to improve disintegration in
   the stomach.
4. Surfactants (Solubilizers)
   ✔ Purpose: Enhances the solubility and absorption of herbal bioactives.
   ✔ Commonly Used In: Liquid formulations, Soft gels
   Examples:
    Polysorbates (Tween 80, Tween 20)
    Lecithin (Soy Lecithin, Egg Lecithin)
    Sodium Lauryl Sulfate (SLS)
    Glycerol Monostearate
   Example: Lecithin is used in curcumin-based herbal formulations to improve bioavailability.
5. Lubricants (Prevent Sticking & Improve Flowability)
   ✔ Purpose: Reduces friction during tablet compression and prevents sticking to
   manufacturing equipment.
   ✔ Commonly Used In: Tablets, Capsules
   Examples:
    Magnesium Stearate
    Stearic Acid
    Talc
    Polyethylene Glycol (PEG)
   Example: Magnesium stearate is used in herbal tablets like Brahmi and Shatavari to improve
   flow properties.
6. Coating Agents (Protective Coatings)
   ✔ Purpose: Improves stability, taste, and appearance of herbal tablets by providing a
   protective coating.
   ✔ Commonly Used In: Tablets, Capsules
   Examples:
    Hydroxypropyl Methylcellulose (HPMC)
    Shellac
    Ethyl Cellulose
    Pectin
   Example: HPMC coating is used in neem tablets to mask bitterness.
7. Preservatives (Microbial Growth Inhibitors)
   ✔ Purpose: Prevents microbial contamination and extends shelf life of herbal formulations.
   ✔ Commonly Used In: Syrups, Creams, Herbal Extracts
   Examples:
    Benzoic Acid
    Sodium Benzoate
    Parabens (Methylparaben, Propylparaben)
    Sorbic AcidExample: Sodium benzoate is used in Amla and Aloe Vera syrups to
   prevent fungal growth.
8. Sweeteners & Flavoring Agents
   ✔ Purpose: Masks the bitter taste of herbal extracts and enhances patient compliance.
   ✔ Commonly Used In: Syrups, Lozenges, Tablets
   Examples:
    Natural Sweeteners: Sucrose, Stevia, Honey
    Artificial Sweeteners: Aspartame, Xylitol
    Flavoring Agents: Menthol, Vanillin, Orange Oil
   Example: Stevia is added to herbal cough syrups for natural sweetness.
9. Antioxidants (Prevent Herbal Compound Degradation)
   ✔ Purpose: Protects herbal bioactives from oxidation due to exposure to air or light.
   ✔ Commonly Used In: Oils, Capsules, Herbal Extracts
   Examples:
    Ascorbic Acid (Vitamin C)
    Tocopherols (Vitamin E)
    Butylated Hydroxytoluene (BHT)
    Butylated Hydroxyanisole (BHA)
   Example: Vitamin E is used in herbal skin creams to prevent rancidity.
10. Solvents (Extract Herbal Bioactives)
    ✔ Purpose: Used to dissolve herbal active ingredients for tinctures, syrups, and
    emulsions.
    ✔ Commonly Used In: Liquid herbal formulations
    Examples:
     Water
     Ethanol (Hydroalcoholic Extraction)
     Glycerin
     Propylene Glycol
    Example: Hydroalcoholic extract of Ashwagandha is used in liquid herbal tonics.
    Importance of Excipients in Herbal Formulations
     Enhances stability – Prevents degradation of herbal compounds.
     Improves bioavailability – Helps in better absorption and effectiveness of herbal
    extracts.
     Ensures accurate dosing – Provides uniform weight and distribution of herbal
    actives.
     Improves patient compliance – Enhances taste, appearance, and ease of use.
    Bioavailability refers to the percentage of an administered drug or bioactive compound
    that reaches systemic circulation in an active form and is available for therapeutic action.
    In simple terms, higher bioavailability means more of the active compound is absorbed
    and utilized by the body, leading to better effectiveness.
    Factors Affecting Bioavailability
11. Solubility of the compound – Poorly water-soluble compounds have lower absorption.
12. Absorption in the gastrointestinal (GI) tract – Some compounds are degraded in the
    stomach or intestine before being absorbed.
13. Metabolism (First-Pass Effect) – The liver may metabolize a significant portion of the
    compound before it reaches circulation.
14. Stability – Some compounds degrade due to heat, pH, or enzymatic action.