Pharmaceutical Dosage Forms

Pharmaceutical Dosage Forms

• This presentation covers various pharmaceutical dosage forms, specifically liquid oral preparations.

Types of Oral Solutions

• Oral Solutions: These include syrups, elixirs, linctus, draughts, and oral drops.
• Syrup: A viscous, sweet aqueous preparation containing at least 45% sucrose. Viscosity is due to hydrogen bonds between the sucrose and water molecules.
  • Simple syrup consists of only sucrose and purified water.
  • Medicated syrups contain medicinal substances (e.g., Phenergan syrup).
  • Other syrups can be flavored (non-medicated), containing flavoring agents.
• Elixir: A clear, sweet hydroalcoholic solution intended for oral use and usually flavored. Elixirs containing over 10-12% alcohol are self-preserving.
• Linctus: A viscous preparation of the active ingredient in a high concentration of sucrose. It's used to relieve coughs. Glycerin is added for sweet taste and demulcent action.
• Draught: A larger-volume liquid oral preparation, typically administered in a separate bottle (around 50 ml). Ipecacuanha draught is an example used to induce vomiting.
• Oral Drops: A liquid preparation typically for pediatrics and contains vitamins. Drops are supplied in bottles with calibrated droppers.
• Dry Powder for Solution: A dry powder that is reconstituted with a vehicle (like water). This is often used for unstable drugs like antibiotics. The resulting solution or suspension is stored in well-dried bottles in a cool, dark place.
  • The solution remains stable after reconstitution for 7-14 days, depending on storage conditions.
  • Penicillin V potassium solution is an example.

Liquid For Cutaneous Application

• Lotions: Aqueous, alcoholic, or oily preparations (mono or biphasic systems) that are applied to unbroken skin, without rubbing.
• Liniments: Alcoholic or oleaginous solutions or emulsions applied with rubbing to the unbroken skin. Alcoholic liniments serve as rubefacients & counter irritants. Oleaginous liniments are used for massage.
• Paints: Solutions or dispersions of active ingredients intended for application to skin or mucous membranes. They contain volatile solvents that evaporate quickly, leaving a dry film.
• Collodion: A liquid preparation containing pyroxylin (nitrocellulose) in a mixture of ether and ethanol. This forms a protective film on surfaces. Collodion is made flexible by adding castor oil (a plasticizer). Pyroxylin is highly flammable and is stored in closed containers, protected from light. Salicylic Acid Collodion USP is a medicated liquid used for corns and warts.

Types of Oromucosal Liquids

• Mouth Wash: Therapeutic & cosmetic liquids used for the mouth. They can be used for gum problems.
• Gargles: Aqueous solutions often containing antiseptics, antibiotics, and/or anesthetics, used for treating the throat and nasopharynx.
• Gingival & Sublingual Preparations: Include sprays or drops for specific areas of oral mucosa, like gums during teething. They may be absorbed systematically.
• Topical Oral Dental Solutions: Include benzocaine (anesthetic) for pain relief and eugenol for dental cavities.

Solutions Administered into Body Cavities

• Douches/ Irrigations: Sterile isotonic aqueous solutions for cleansing of body cavities and wounds. Examples include eye douches, pharyngeal douches, nasal, and vaginal douches, as well as ear washes.
• Rectal Solutions (Enemas): Aqueous or oily solutions for rectal administration of medications in cleansing, diagnostic, or therapeutic situations. Enemas can be for retention (e.g., hydrocortisone), for evacuation (e.g., docusate potassium), or diagnostic purposes (e.g., Barium Sulphate).
• Nasal Solutions: Aqueous solutions, administered in drops or sprays for various purposes like reducing congestion. Intranasal drug administration can also offer rapid absorption into systemic circulation.
• Otic/ Aural Solutions: Topical preparations like glycerin/water solutions for the ear, usually including anesthetics, antibiotics, and anti-inflammatory agents.
• Ocular Solutions (Ophthalmic Solutions): Small-volume, isotonic, sterile liquid solutions for instillation into the eyes. The solutions often have specific pH and viscosity to ensure stability and comfort.

Miscellaneous Liquids

• Extracts & Tinctures: Concentrated solutions of active principles from animal or plant sources. Extracts are more concentrated than tinctures.
• Spirits: Alcoholic solutions of volatile materials used mainly as flavoring agents.
• Infusion & Decoctions: Herbal preparations where ingredients are steeped in liquid (often water) to extract their properties.
• Aromatic Water: Water infused with flavoring agents, such as aromatic herbs or flowers.

Viscid Solutions

• Glycerins/Glycerites: Solutions or mixtures of medicinal substances in glycerol (minimum 50% glycerol).
• Oleo Vitamins: Preparations of fat-soluble vitamins (such as vitamins A & D) dissolved in edible vegetable oil. They should be stored in tight containers, preferably under inert gas, to avoid rancidity.

Additional Notes

• The provided pages contain examples of formulations and labeling requirements for different solution types.
• Several case studies illustrate the potential use of different solution types in various medical situations, including muscle soreness, buccal ulcers and their appropriate usage.