| Alcohol | Solvent/Preservative | ⚠️ Yes — Alcohol | Ethanol (ethyl alcohol) used as a solvent, preservative, or extraction agent. Present in many liquid formulations. May be relevant for patients avoiding alcohol for medical or religious reasons. |
| Isostearyl Alcohol? | Emollient/Emulsifier | ?Uncertain — Stearyl Alcohol | A branched-chain fatty alcohol used as an emollient and emulsifier in topical formulations. |
| Peg/ppg-18/18 Dimethicone | Emulsifier/Skin Conditioner | ⚠️ Yes — PEG | A silicone-based emulsifier combining PEG and polypropylene glycol with dimethicone. Used in topical formulations for smooth application. |
| Sodium Metabisulfite | Antioxidant/Preservative | ⚠️ Yes — Sulfite | A sulfite compound used as an antioxidant and preservative. Can trigger severe reactions (bronchospasm, anaphylaxis) in sulfite-sensitive individuals, particularly asthmatics. |
| .alpha.-tocopherol | Antioxidant | No | The most biologically active form of vitamin E. Used to protect formulations from oxidative degradation. |
| Aluminum Hydroxide | Antacid/Adjuvant | No | An aluminum salt used as an antacid ingredient and as an adjuvant in some vaccine formulations. |
| Barium Sulfate | — | No | — |
| Butylene Glycol | Humectant/Solvent | No | A synthetic glycol used as a humectant and solvent in topical formulations. Helps products spread smoothly on skin. |
| Corn Oil? | Solvent/Vehicle | No | Oil extracted from corn germ, used as a solvent and vehicle in oral formulations. Must be avoided by individuals with corn allergy. |
| Dimethicone 20 | Skin Protectant | No | A silicone-based polymer used as a skin protectant, emollient, and anti-foaming agent in topical formulations. |
| Dimethiconol/trimethylsiloxysilicate Crosspolymer (40/60 W/w; 1000000 Pa.s)? | Skin Conditioner | No | A silicone elastomer blend used in topical formulations to provide a smooth, silky feel and improve product spreadability. |
| Edetate Trisodium | — | No | — |
| Ferric Oxide Red | Colorant | No | Red iron oxide pigment used in tablet coatings and capsule shells. A mineral-based colorant, distinct from FD&C synthetic dyes. |
| Ferric Oxide Yellow | Colorant | No | Yellow iron oxide pigment used in tablet coatings and capsule shells. A mineral-based colorant. |
| Ferrosoferric Oxide | Colorant | No | Black iron oxide used as a pigment in tablet coatings and capsule shells. Derived from iron, not from food allergen sources. |
| Glycerin | Humectant/Solvent | No | A sugar alcohol that attracts moisture. Used as a humectant, solvent, and sweetener in many oral and topical medications. Generally well tolerated. |
| Glyceryl Isostearate? | Emulsifier | No | A glycerin ester used as an emulsifier and skin-conditioning agent in topical formulations. |
| Glycine | Buffer/Stabilizer | No | The simplest amino acid. Used as a buffer, stabilizer, and tonicity agent in injectable formulations. |
| Hamamelis Virginiana Top Water | Skin Conditioner | No | Witch hazel distillate, a plant-derived astringent used in topical formulations to soothe and tone the skin. |
| Microcrystalline Wax? | Stiffening Agent | No | A petroleum-derived wax used to adjust consistency in ointments and as a coating agent. |
| Phenoxyethanol | Preservative | No | A synthetic preservative used to prevent microbial growth in topical and some oral formulations. Can cause skin irritation in sensitive individuals. |
| Polysorbate 80 | Emulsifier/Solubilizer | No | A non-ionic surfactant used to dissolve and stabilize ingredients that do not mix well with water. Derived from sorbitol and oleic acid. Rare hypersensitivity reactions reported. |
| Sodium Acetate Anhydrous? | Buffer | No | A sodium salt of acetic acid used as a buffering agent in injectable and ophthalmic solutions. |
| Sodium Stearyl Fumarate? | Lubricant | No | A tablet lubricant used as an alternative to magnesium stearate. Vegetable-derived. |
| Stearalkonium Chloride? | Conditioning Agent | No | A quaternary ammonium compound used as a conditioning and antistatic agent in topical formulations. |
| Stearic Acid | Lubricant | No | A fatty acid used as a lubricant in tablet manufacturing. |
| Talc | Glidant/Lubricant | No | A mineral used to improve powder flow in manufacturing. |
| Threonine? | — | No | — |
| Trehalose Dihydrate | Stabilizer/Cryoprotectant | No | A natural disaccharide used to stabilize proteins in freeze-dried formulations and to protect biological products. |
| Zinc Oxide | — | No | — |