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Introduction
1. Medications
1.1 Generic names and brand names
1.2 Classification of medications
1.3 Drug interactions and contraindications
1.4 Medications by organ system
1.5 Drug strengths, dose, and dosage forms
1.6 Routes of administration and special handling of drugs
1.7 Medication side effects, adverse effects and allergies
1.8 Indications of medications and dietary supplements
1.9 Drug stability
1.10 Narrow therapeutic index (NTI) medications
1.11 Pharmaceutical incompatibilities
1.12 Proper storage of medications
1.13 Vaccine types and schedules
2. Patient safety and quality assurance
3. Order entry and processing
4. Federal requirements
Wrapping up
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1.5 Drug strengths, dose, and dosage forms
Achievable PTCE
1. Medications
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Drug strengths, dose, and dosage forms

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Definitions
Drug strength
The amount of drug in a given dosage form. It tells you how much active ingredient is in each unit, such as one tablet or one capsule. For example, a Tylenol 500 mg tablet has a strength of 500 mg, meaning it contains 500 mg of the active ingredient acetaminophen. Strength is usually written as a number followed by a unit abbreviation (e.g., g, g/dL, IU, mg). A medication may come in multiple strengths; for example, Tylenol is sold in 325 mg, 500 mg, and 650 mg strengths.
Dose
The amount of drug given at one time. For example, the dose of Tylenol for adults and children 12 years and older might be 650 mg (regular strength) or 1000 mg (extra strength). A dose can be expressed in milligrams (mg), milliliters (mL), or other units such as puffs (inhalers), drops, or counts (e.g., two capsules or three tablets).
Dosage
A broad term that includes how much medication to take at once, how often to take it, and for how long. For example, a Tylenol dosage instruction from the label might read: “For adults and children 12 years and over: For minor aches and pains, take two tablets of Regular Strength Tylenol every four to six hours as needed. Do not take more than ten tablets in 24 hours.”
Dosage form
The physical form in which a drug is manufactured or administered. The dosage form depends on the route of administration (e.g., oral, intravenous, through the skin). A drug may be available in more than one dosage form.

Based on their physical form, drugs can be classified as solids, semisolids, liquids, and gases.

Types of solid drug forms

  1. Tablets: Solid dosage forms containing the active drug with or without excipients. Excipients are substances other than the active drug and may include binders, fillers, preservatives, emulsifiers, and solvents. Tablets come in different forms:

    • Chewable tablets are chewed before swallowing.
    • Oral disintegrating tablets (ODTs) dissolve in the mouth.
    • Sublingual tablets (e.g., sublingual nitroglycerine) dissolve rapidly when kept under the tongue and are useful when rapid action is required (e.g., in heart attacks).
    • Effervescent tablets dissolve quickly in liquids like water (e.g., Alka-Seltzer tablets).
    • Buccal tablets are kept on the inside of the cheek.
Sublingual region
Sublingual region
Buccal region
Buccal region

  1. Pills: Small, round, or oval medicinal products that are swallowed and contain active drugs with excipients.

  2. Capsules: Solid dosage forms in which the drug(s) are enclosed within a shell made of gelatin or other substances. Capsules may be:

    • Hard or soft gelatin capsules
    • Modified-release capsules, where the release rate of the active ingredient is altered
    • Enteric capsules, which release the active ingredient in the intestine
    • Sprinkle capsules, which contain small granules inside the capsule shell; the capsule may be swallowed whole or opened so the pellets can be mixed with food or beverages and swallowed

  3. Caplets: Small tablets coated with a film or gelatin to make them easier to swallow.

  4. Gelcaps: Soft gelatin forms that contain the active drug in solid or liquid form. They are absorbed more quickly and are often easier to swallow. Some pain medications, such as Tylenol, are available in gelcaps.

  5. Powders: Finely divided particles in micron sizes.

  6. Granules: Aggregates of powders.

  7. Lozenges: Flat tablets made of edible gum and sugar, used to medicate the mouth and throat.

  8. Pastilles: Hard, jelly-like forms that contain glycerin and gelatin.

Administering oral medications
Administering oral medications

Types of semi-solid drug forms

  1. Cream: Creams contain more than 20% water or volatile components and typically less than 50% hydrocarbons, waxes, or polyols as vehicles.
  2. Ointment: Semisolid preparations used topically for protective emollient effects or as a vehicle for local medication administration. Their bases are mixtures of fats, waxes, animal and plant oils, and solid and liquid hydrocarbons.
  3. Paste: A semisolid preparation that includes a fatty base and at least 25% of medication.
  4. Gel: Semi-solid dosage forms with a hydrophilic or hydrophobic base mixed with a gelling agent.
  5. Suppository: Dosage forms inserted into body orifices such as the rectum, vagina, or ear. They act locally.
  6. Patch: Also called transdermal patches. These are adhesive, medicated patches applied to the skin that allow medication to be absorbed through the skin into the bloodstream.
  7. Poultice: Also called a cataplasm. A soft, moist mass that is often heated and medicated, spread on a cloth, and applied over the skin to treat an aching, inflamed, or painful body part.
Transdermal patch
Transdermal patch

Types of liquid drug forms

  1. Syrup: A thick, sweet liquid used as a carrier for drugs or as a flavoring agent.
  2. Elixir: Clear liquid dosage forms containing sugar, water, and alcohol.
  3. Solution: A clear liquid preparation used for internal or external applications.
  4. Emulsion: A biphasic liquid dosage form in which two or more liquids are mixed with the help of an emulsifier (e.g., an oil-in-water emulsion).
  5. Suspension: Biphasic liquid forms in which fine solid particles are suspended in a liquid medium.
  6. Lotion: A low- to medium-viscosity liquid dosage form applied to the skin.
  7. Enema: A liquid dosage form inserted rectally.
  8. Liniment: A liquid dosage form containing a mixture of oil, alcohol, soap, etc., that is rubbed into the skin.
  9. Tincture: A solution of medication in alcohol (e.g., tincture iodine).
Tincture iodine
Tincture iodine

Types of gaseous drug forms

  1. Aerosols: Suspensions of fine solid or liquid particles in gas. They are used to apply drugs to the respiratory tract. The mixture is stored in a container under high pressure and released as a fine mist.
  2. Sprays: A type of aerosol in which the medication is applied as a wet spray (e.g., nasal sprays).
  3. Gasses: Inhaled for anesthesia (e.g., nitrous oxide) or for other purposes (e.g., oxygen).

Drug strength, dose, dosage, and dosage form

  • Drug strength: amount of active ingredient per unit (e.g., mg/tablet)
  • Dose: amount of drug given at one time (e.g., 650 mg)
  • Dosage: how much, how often, and duration of medication use
  • Dosage form: physical form of drug (e.g., tablet, capsule, liquid)

Types of solid drug forms

  • Tablets: solid forms with active drug and excipients; types include chewable, ODTs, sublingual, effervescent, buccal
  • Capsules: drug enclosed in gelatin shell; types include hard/soft, modified-release, enteric, sprinkle
  • Other forms: pills, caplets, gelcaps, powders, granules, lozenges, pastilles

Types of semi-solid drug forms

  • Creams, ointments, pastes, gels: topical preparations with varying water/fat content
  • Suppositories: inserted into body orifices for local action
  • Transdermal patches: adhesive medicated patches for systemic absorption
  • Poultices: heated, medicated moist masses applied to skin

Types of liquid drug forms

  • Syrup, elixir: sweet or alcohol-based oral liquids
  • Solution, emulsion, suspension: clear or biphasic liquids for internal/external use
  • Lotion, enema, liniment, tincture: applied to skin or administered rectally; tincture contains alcohol

Types of gaseous drug forms

  • Aerosols: fine particles in gas for respiratory delivery
  • Sprays: wet medication mist (e.g., nasal sprays)
  • Gases: inhaled for anesthesia or oxygen therapy

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Drug strengths, dose, and dosage forms

Definitions
Drug strength
The amount of drug in a given dosage form. It tells you how much active ingredient is in each unit, such as one tablet or one capsule. For example, a Tylenol 500 mg tablet has a strength of 500 mg, meaning it contains 500 mg of the active ingredient acetaminophen. Strength is usually written as a number followed by a unit abbreviation (e.g., g, g/dL, IU, mg). A medication may come in multiple strengths; for example, Tylenol is sold in 325 mg, 500 mg, and 650 mg strengths.
Dose
The amount of drug given at one time. For example, the dose of Tylenol for adults and children 12 years and older might be 650 mg (regular strength) or 1000 mg (extra strength). A dose can be expressed in milligrams (mg), milliliters (mL), or other units such as puffs (inhalers), drops, or counts (e.g., two capsules or three tablets).
Dosage
A broad term that includes how much medication to take at once, how often to take it, and for how long. For example, a Tylenol dosage instruction from the label might read: “For adults and children 12 years and over: For minor aches and pains, take two tablets of Regular Strength Tylenol every four to six hours as needed. Do not take more than ten tablets in 24 hours.”
Dosage form
The physical form in which a drug is manufactured or administered. The dosage form depends on the route of administration (e.g., oral, intravenous, through the skin). A drug may be available in more than one dosage form.

Based on their physical form, drugs can be classified as solids, semisolids, liquids, and gases.

Types of solid drug forms

  1. Tablets: Solid dosage forms containing the active drug with or without excipients. Excipients are substances other than the active drug and may include binders, fillers, preservatives, emulsifiers, and solvents. Tablets come in different forms:

    • Chewable tablets are chewed before swallowing.
    • Oral disintegrating tablets (ODTs) dissolve in the mouth.
    • Sublingual tablets (e.g., sublingual nitroglycerine) dissolve rapidly when kept under the tongue and are useful when rapid action is required (e.g., in heart attacks).
    • Effervescent tablets dissolve quickly in liquids like water (e.g., Alka-Seltzer tablets).
    • Buccal tablets are kept on the inside of the cheek.

  1. Pills: Small, round, or oval medicinal products that are swallowed and contain active drugs with excipients.

  2. Capsules: Solid dosage forms in which the drug(s) are enclosed within a shell made of gelatin or other substances. Capsules may be:

    • Hard or soft gelatin capsules
    • Modified-release capsules, where the release rate of the active ingredient is altered
    • Enteric capsules, which release the active ingredient in the intestine
    • Sprinkle capsules, which contain small granules inside the capsule shell; the capsule may be swallowed whole or opened so the pellets can be mixed with food or beverages and swallowed

  3. Caplets: Small tablets coated with a film or gelatin to make them easier to swallow.

  4. Gelcaps: Soft gelatin forms that contain the active drug in solid or liquid form. They are absorbed more quickly and are often easier to swallow. Some pain medications, such as Tylenol, are available in gelcaps.

  5. Powders: Finely divided particles in micron sizes.

  6. Granules: Aggregates of powders.

  7. Lozenges: Flat tablets made of edible gum and sugar, used to medicate the mouth and throat.

  8. Pastilles: Hard, jelly-like forms that contain glycerin and gelatin.

Types of semi-solid drug forms

  1. Cream: Creams contain more than 20% water or volatile components and typically less than 50% hydrocarbons, waxes, or polyols as vehicles.
  2. Ointment: Semisolid preparations used topically for protective emollient effects or as a vehicle for local medication administration. Their bases are mixtures of fats, waxes, animal and plant oils, and solid and liquid hydrocarbons.
  3. Paste: A semisolid preparation that includes a fatty base and at least 25% of medication.
  4. Gel: Semi-solid dosage forms with a hydrophilic or hydrophobic base mixed with a gelling agent.
  5. Suppository: Dosage forms inserted into body orifices such as the rectum, vagina, or ear. They act locally.
  6. Patch: Also called transdermal patches. These are adhesive, medicated patches applied to the skin that allow medication to be absorbed through the skin into the bloodstream.
  7. Poultice: Also called a cataplasm. A soft, moist mass that is often heated and medicated, spread on a cloth, and applied over the skin to treat an aching, inflamed, or painful body part.

Types of liquid drug forms

  1. Syrup: A thick, sweet liquid used as a carrier for drugs or as a flavoring agent.
  2. Elixir: Clear liquid dosage forms containing sugar, water, and alcohol.
  3. Solution: A clear liquid preparation used for internal or external applications.
  4. Emulsion: A biphasic liquid dosage form in which two or more liquids are mixed with the help of an emulsifier (e.g., an oil-in-water emulsion).
  5. Suspension: Biphasic liquid forms in which fine solid particles are suspended in a liquid medium.
  6. Lotion: A low- to medium-viscosity liquid dosage form applied to the skin.
  7. Enema: A liquid dosage form inserted rectally.
  8. Liniment: A liquid dosage form containing a mixture of oil, alcohol, soap, etc., that is rubbed into the skin.
  9. Tincture: A solution of medication in alcohol (e.g., tincture iodine).

Types of gaseous drug forms

  1. Aerosols: Suspensions of fine solid or liquid particles in gas. They are used to apply drugs to the respiratory tract. The mixture is stored in a container under high pressure and released as a fine mist.
  2. Sprays: A type of aerosol in which the medication is applied as a wet spray (e.g., nasal sprays).
  3. Gasses: Inhaled for anesthesia (e.g., nitrous oxide) or for other purposes (e.g., oxygen).
Key points

Drug strength, dose, dosage, and dosage form

  • Drug strength: amount of active ingredient per unit (e.g., mg/tablet)
  • Dose: amount of drug given at one time (e.g., 650 mg)
  • Dosage: how much, how often, and duration of medication use
  • Dosage form: physical form of drug (e.g., tablet, capsule, liquid)

Types of solid drug forms

  • Tablets: solid forms with active drug and excipients; types include chewable, ODTs, sublingual, effervescent, buccal
  • Capsules: drug enclosed in gelatin shell; types include hard/soft, modified-release, enteric, sprinkle
  • Other forms: pills, caplets, gelcaps, powders, granules, lozenges, pastilles

Types of semi-solid drug forms

  • Creams, ointments, pastes, gels: topical preparations with varying water/fat content
  • Suppositories: inserted into body orifices for local action
  • Transdermal patches: adhesive medicated patches for systemic absorption
  • Poultices: heated, medicated moist masses applied to skin

Types of liquid drug forms

  • Syrup, elixir: sweet or alcohol-based oral liquids
  • Solution, emulsion, suspension: clear or biphasic liquids for internal/external use
  • Lotion, enema, liniment, tincture: applied to skin or administered rectally; tincture contains alcohol

Types of gaseous drug forms

  • Aerosols: fine particles in gas for respiratory delivery
  • Sprays: wet medication mist (e.g., nasal sprays)
  • Gases: inhaled for anesthesia or oxygen therapy