Pharmaceutical and cosmetic ingredients are specialized substances used in the formulation of medicines and personal care products, each serving distinct but sometimes overlapping functions. In pharmaceuticals, ingredients are categorized into active pharmaceutical ingredients (APIs), which provide therapeutic effects, and excipients, which support drug delivery, stability, and absorption. Common examples include paracetamol (API), lactose (excipient), and magnesium stearate (lubricant). In cosmetics, ingredients are used for skin care, hair care, and beautification, including emollients (like shea butter), humectants (such as glycerin), preservatives, fragrances, and active agents like hyaluronic acid, retinol, or salicylic acid. Both industries prioritize purity, safety, and regulatory compliance, with a growing trend toward natural and sustainable raw materials.