Topical Dosage Forms Overview
📌 Topical dosage forms are preparations applied to the skin or mucous membranes, categorized into three physical forms: solid, semi-solid, and liquid.
🧪 Solid topical dosage forms are primarily discussed as powder, which is a dry mixture suitable for large surfaces and folded skin areas due to its absorbent properties.
💊 Semi-solid preparations are the most common category, including ointments, creams, gels, and pastes.
💧 Liquid preparations include solutions, tinctures (alcohol vehicle), and lotions (oil and water mixture).

Specific Organ Topical Preparations
👁️ Ophthalmic preparations (eye drops and eye ointments) must be sterile, non-irritative, and isotonic with tear fluid for drops.
👂 Otic preparations are administered into the ear canal, offering high local drug concentration compared to systemic administration.
💨 Inhalation forms, such as aerosols, use fine particles (e.g., < 2 microns for alveolar deposition) to treat airways, aiming for local or systemic effects.
🌡️ Vaginal dosage forms include tablets, gels, creams, or suppositories, often used for antiseptic, antibacterial, or contraceptive local effects.

Advanced Topical Delivery Systems
🧱 Pastes are semi-solid preparations containing a high concentration (> 50%) of undissolved powder, making them thicker, less oily, and capable of absorbing secretions.
🌬️ Lotions are water-based mixtures suitable for hairy areas or oozing lesions because they spread easily and feel light.
🔄 Transdermal preparations are designed to pass the drug through the skin into the systemic circulation, avoiding first-pass liver metabolism.

Key Points & Insights
➡️ Ointments are preferable for dry skin due to their occlusive, protective, and moisturizing effects.
➡️ Gels are favored when a non-greasy formulation with good spreadability and a cooling effect is needed.
➡️ Eye ointments offer longer active drug substance exposure but may cause temporary vision blurring, making them suitable for overnight use.
➡️ Topical drug administration to the ear offers rapid delivery and high local concentration but carries the risk of ototoxicity with high drug concentrations.

📸 Video summarized with SummaryTube.com on Nov 17, 2025, 13:04 UTC