Dosage forms (also called unit doses) are essentially pharmaceutical drug products in the form in which they are marketed for use, typically involving a mixture of active drug components and nondrug components (excipients), along with other non-reusable material that may not be considered either ingredient or packaging (such as a capsule shell, for example). The term unit dose can also sometimes encompass non-reusable packaging as well (especially when each drug product is individually packaged), although the FDA distinguishes that by unit-dose "packaging" or "dispensing". Depending on the context, multi(ple) unit dose can refer to distinct drug products packaged together, or to a single drug product containing multiple drugs and/or doses. The term dosage form can also sometimes refer only to the pharmaceutical formulation of a drug product's constituent drug substance(s) and any blends involved, without considering matters beyond that (like how it is ultimately configured as a consumable product such as a capsule, patch, etc.). Because of the somewhat vague boundaries and unclear overlap of these terms and certain variants and qualifiers thereof within the pharmaceutical industry, caution is often advisable when conversing with someone who may be unfamiliar with another person's use of the term.
Depending on the method/route of administration, dosage forms come in several types. These include many kinds of liquid, solid, and semisolid dosage forms. Common dosage forms include pill, tablet, or capsule, drink or syrup, and natural or herbal form such as plant or food of sorts, among many others. Notably, the route of administration (ROA) for drug delivery is dependent on the dosage form of the substance in question. A liquid dosage form is the liquid form of a dose of a chemical compound used as a drug or medication intended for administration or consumption.
Various dosage forms may exist for a single particular drug, since different medical conditions can warrant different routes of administration. For example, persistent nausea and emesis or vomiting may make it difficult to use an oral dosage form, and in such a case, it may be necessary to use an alternative route such as inhalational, buccal, sublingual, nasal, suppository or parenteral instead. Additionally, a specific dosage form may be a requirement for certain kinds of drugs, as there may be issues with various factors like chemical stability or pharmacokinetics. As an example, insulin cannot be given orally because upon being administered in this manner, it is extensively metabolized in the gastrointestinal tract (GIT) before reaching the blood stream, and is thereby incapable of sufficiently reaching its therapeutic target destinations. The oral and intravenous doses of a drug such as paracetamol will differ for the same reason.
- Pill, i.e. tablet or capsule syrups
- Specialty tablet like buccal, sub-lingual, or orally-disintegrating
- Thin film (e.g., Listerine Pocketpaks)
- Liquid solution or suspension (e.g., drink or syrup)
- Powder or liquid or solid crystals
- Natural or herbal plant, seed, or food of sorts (e.g., marijuana such as that found in "Space Cake")
- Pastes (e.g., Toothpaste)
- Intradermal (ID)
- Subcutaneous (SC)
- Intramuscular (IM)
- Intraosseous (IO)
- Intraperitoneal (IP)
- Cream, gel, liniment or balm, lotion, or ointment, etc.
- Ear drops (otic)
- Eye drops (ophthalmic)
- Skin patch (transdermal)
- Vaginal rings
- Dermal patch