Dosage Form Terminology

Back to RX 421 - Intro to Dosage Forms

Dosage forms by route of administration
Note that the same dosage form may be given by different routes.

Oral

 * tablets
 * capsules
 * solutions
 * syrups
 * elixirs
 * suspensions
 * gels
 * powders

Sublingual

 * tablets
 * troches or lozenges

Parenteral

 * solutions
 * suspensions/emulsion

Epicutaneous/Transdermal

 * ointments
 * creams
 * infusion pumps
 * pastes
 * plasters
 * powders
 * aerosols
 * lotions
 * transdermal patches, discs, solutions

Conjunctival

 * contact lens inserts
 * ointments

Intraocular

 * solutions

Intranasal

 * solutions
 * sprays
 * inhalants
 * ointments

Intrarespiratory

 * aerosols

Rectal

 * solutions
 * ointments
 * suppositories

Vaginal

 * solutions
 * ointments
 * emulsion foams
 * tablets
 * inserts, suppositories, sponge

Urethral

 * solutions
 * suppositories

Characteristics of Dosage Forms
A brief explanation of each of the dosage form types.

Aerosols
A pressurized spray of fine or liquid particles suspended in a gas or air
 * Key Features: Spray, fine mist
 * Advantages: Less messy
 * Disadvantages: More expensive, some are environmental hazards

Capsules
A small soluble container, usually made of gelatin that encloses a dose of an oral medication.
 * Key Features: Generally small in size, gelatin container
 * Advantages: Ease of swallow. Timed release delivery. Able to hold more than more medication.
 * Disadvantages: Can in turn be difficult to swallow. Slower delivery of medication.

Creams
Are a semisolid and are generally thick with the drug dispersed throughout.
 * Key Features: Semisolid preparation, local
 * Advantages: Less greasy and lighter than ointment
 * Disadvantages: Limited absorption

Elixirs
A liquid that contains water, alcohol, sweeteners, or flavors, used mostly as a way to administer drugs orally.
 * Key Features: Sweet, alcoholic, aqueous
 * Advantages: Used to mask bitter or nauseous drugs
 * Disadvantages: Alcohol, oral only route of administration

Emulsions
A suspension of globules of one liquid in a second liquid with which the first will not mix.
 * Key Features: Two phase liquid that has both parts un-dissolved.
 * Advantages: Able to deliver more than one substance, but in one form.
 * Disadvantages: Stability. Requires constant shaking. Susceptible to microbial growth.

Enteric Coating
A coating, around a tablet, that inhibits the dissolving of the tablet in the stomach. Allows dissolving of tablet to take place in the intestine when the drug is destroyed by gastric secretions.

Gels
A suspension that is firm (like a jelly) even though it contains a large amount of liquid, used to administer drugs than cannot be dissolved.
 * Key Features: Colloid particles, jelly like, thickening agent
 * Advantages: Local
 * Disadvantages: Sticky, limited absorption

Implantable Devices
pellets that are placed under skin and provide continuous release of medication.
 * Key Features: Placed under skin, mandatory compliance
 * Advantages: Continuous release
 * Disadvantages: Allergic reactions, delayed onset, side effects

Inhalations
A medication or drug that is in vapor form and can be inhaled into lungs.
 * Key Features: A gas, vapor, or aerosol that contains a medication.
 * Advantages: Carry drug directly to nose, throat, and lungs.
 * Disadvantages: General short duration of medication. Limited medications that can be delivered this way.

Lotions
a medical liquid that is applied externally (on the outside) to protect the skin or to treat a skin disorder.
 * Key Features: Liquid, applied externally, local
 * Advantages: A medium for a variety of medications
 * Disadvantages: messy, limited absorption

Lozenges
A small, medicated (containing a drug) candy that is intended to be dissolved in the mouth.
 * Key Features: Disc. Shaped. Generally a flavored substance intended to be dissolved slowly in the mouth.
 * Advantages: Delivers medication directly to mouth or throat. Can deliver a multitude of drugs.
 * Disadvantages: Can take long time for delivery of drug.

Ointments
A highly viscous or semisolid substance used on the skin as a cosmetic, an emollient, or a medicament.
 * Key Features: Semisolid substance used to deliver certain medications.
 * Advantages: Variety of medication(s) that can be delivered.
 * Disadvantages: Limited to localized and/or area specific delivery.

Parenterals
administration by any way other than the mouth: injection examples: intradermal, intramuscular, intraorbital, intravenous, intraspinal, intrasternal, subcutaneous.
 * Key Features: Avoid gut (irritation)
 * Advantages: Good dosage form when oral is not possible, faster absorption
 * Disadvantages: increase risk to patient (infection)

Pessaries
A device that is placed in the vagina that can be used for uterine support, a device to prevent conception, or a suppository to deliver a medication (drug).
 * Key Features: Globular and/or cone shaped.
 * Advantages: Localized delivery of medication and/or uterine support.
 * Disadvantages: Limits to local action only.

Powders
A substance consisting of ground, pulverized, or otherwise finely dispersed solid particles.
 * Key Features: Fine, ground, and pulverized solid particles.
 * Advantages: Able to deliver medication to large area.
 * Disadvantages: Limited amount of drug delivery. Sometimes difficult to apply correctly.

Solutions
A homogeneous mixture of two or more substances, which may be solids, liquids, gases, or a combination of these.
 * Key Features: A clear and uniformly “mixed” preparation.
 * Advantages: Ease of delivery of medication or other substance.
 * Disadvantages: Limited solubility. Limited medication(s) in solution form.

Suppositories
A small plug of medication designed to melt at body temperature within a body cavity other than the mouth, especially the rectum or vagina.
 * Key Features: Cylindrical, about 1 & ½ inches long and can be shaped.
 * Advantages: Gives alternative to oral dosing.
 * Disadvantages: Limited amount of varying medication in suppository form.
 * Cocoa butter suppositories are no longer made because cocoa butter can change crystalline form thus changing the important melting point of the suppository.

Suspensions
Preparations containing finely divided drug particles distributed somewhat uniformly.
 * Key Features: Drug evenly distributed upon shaking
 * Advantages: Some are in ready-to-use form
 * Disadvantages: Available in dry powders, the drug has to be shaken

Syrups
A liquid that is sometimes used as a device to deliver oral medication.
 * Key Features: Thick, sugary, liquid
 * Advantages: Ease of swallow. Pleasant tasting. Little or no alcohol.
 * Disadvantages: Contains sugar; therefore, not all people can take medication that comes in syrup form (i.e.-diabetic patients). Not all drugs are compatible with contents of syrup(s).

Tablets
A small solid pellet of medication to be taken orally.
 * Key Features: May vary in size, shape, weight, hardness, thickness, and dissolving characteristics.
 * Advantages: Patient convenience. Various shapes, colors, and sizes.
 * Disadvantages: Slower delivery of medication.

Topicals
Used for the route of administration of the drug that is applied directly to the part of the body being treated (e.g. to the skin or eye)
 * Key Features: Localized, skin penetration
 * Advantages: Local
 * Disadvantages: Expensive, ensure compliance

Transdermal Patches
A medicated adhesive pad that is placed on the skin to deliver a time-release dose of medication through the skin into the bloodstream.
 * Key Features: Available in forms that control the rate of drug delivery through the skin or that allow the skin to control the rate of drug absorption.
 * Advantages: Patient convenience. Delivers a constant and steady amount of desired medication.
 * Disadvantages: Unsuitable for drugs that may cause irritation to skin. Also, the patches may not adhere well to all skin types.

Pharmaceutical Terminology

 * Absorption - the passage of substance s (i.e. liquids and solids) across and into tissues.
 * Aesthetics - Physical appearance of a medication form.
 * Bioavailability - The extent to which a drug or other substance becomes available at the site of activity after administration.
 * Biotechnological Products - use of living biological things in drug products.
 * Colloidal Dispersions - a colloidal dispersion is one in which particle size is very small and spreads out slowly in liquid.
 * Communition - making particle size smaller and finer.
 * Compaction - The act of pressing and/or joining together.
 * Container - is the device that holds a drug and is, or may be, in direct contact with the drug.
 * Disintegration - The act of reducing to components, fragments, or particles.
 * Dissolution - the separation of a complex chemical into simpler molecules.
 * Distribution - the act of diffusing or spreading over an area.
 * Dosage Form - The form in which a medication is placed to be delivered to the patient. Examples would include: tablets, capsules, injectables, inhalations, patches, etc.
 * Drug Metabolism - conversion of drugs into compounds that can be passed through the kidneys.
 * Eutectic Mixture - a mixture consisting of a solid and a liquid.
 * Excretion - the removal of a drug and its products produced by the body.
 * Heterogeneous - differing in structure and quality and composed of unlike parts. Not homogeneous.
 * Homogeneous - Of the same or similar nature or kind.
 * Impalpable - Unable to touch or grasp with hands.
 * Isotonic - Having the same concentration of solutes as the blood
 * Normal Saline - An isotonic solution that is used in the delivery of certain medication forms, and also used in rehydration.
 * Pharmaceutics - The science of preparing and dispensing drugs.
 * Pharmacokinetics - the study of the ways in which a drug is absorbed, distributed, metabolized and eliminated by the body.
 * Powder Papers - A device (in paper form) that is used in holding powdered medication during measurement and delivery.
 * Quality - degree or grade of excellence.
 * Route of Administration - The route (method of delivery) a medication takes when it is delivered to the patient. Examples - Oral, Intravenously, Intramuscularly, Rectal, etc.
 * Site of Action - the location at which the drug acts upon.
 * Solubility - The amount of a substance that can be dissolved in a given amount of solvent.
 * Spirits - An alcohol solution of a volatile substance.
 * Stability - ability of drugs to keep its original formulation intact.
 * Surfactant - A substance that is used to enhance the spreadability of a drug.
 * Vehicle - A device or structure for transporting substances; a conveyance. A medium through which something is transmitted.

Drug Ingredients

 * Antioxidants - prevents the deterioration of a drug when it is exposed to oxygen and helps to keep a drug stable.
 * Excipient - a physiologically inert substance that is combined with a drug in order to make it possible for administration.
 * Granules - prepared compounds of smaller particles.
 * Preservatives - Substance added to prevent microbial (bacterial) growth, to stabilize a drug, to add color, or to add flavor.
 * Water
 * Bacteriostatic water - sterile water that tends to restrain the development or the reproduction of bacteria.
 * Sterile water for injection - water that is free from living organisms.
 * Distilled water - water that has been treated so that it is free of nonvolatile substances.
 * Tap water - water drawn directly from a tap or faucet and should not be considered pure.

Drug Production

 * Batch - lot of drug with the same level of quality made during a cycle of manufacturing.
 * Bioequivalence - pertaining to a drug that has the same effect on the body as another drug, usually similar in chemical make-up.
 * Extemporaneous Compounding - The act of preparing a medication for a suitable method of delivery.
 * Formulation - (noun) a recipe of the amounts of each ingredient needed to prepare a product. (verb) adjustment of a formula to the amounts desired.
 * Granulation - The act of compacting a mixture and crushing and sizing into small granules.
 * Quality Assurance - A system to check and to provide evidence that something is being done accurately and with high standards.

References Used:

 * Remington: The Science and Practice of Pharmacy, 21st Edition
 * The Bantam Medical Dictionary
 * The Dictionary of Science and Biotechnology
 * Mosby’s Medical, Nursing, and Allied Health Dictionary