Week 7 dosage forms

Question 1

Delivery routes

Answer 1

There are numerous route via which drugs can be administered to the body
Different routes require different dosage forms

Question 2

Dosage forms

Answer 2

When considering dosage forms, we should consider whether we are seeking SYSTEMIC drug delivery or LOCAL drug delivery

Question 3

Systemic drug delivery

Answer 3

Where the drug reaches the site of action through the systemic
(cardiovascular) circulation
Oral dosage forms are the most common type of systemic dosage form

Question 4

Local drug delivery

Answer 4

Drug is delivered directly to the site of action via the dosage form (or the action of the dosage form)

Question 5

Oral dosage forms

Answer 5

-Tablets (and caplets)
-Capsules
-Powders and granules
-Solutions
-Suspensions
-Emulsions

Question 6

Tablets (and caplets)

Answer 6

-Very widely used dosage form formed from compacted powders or granules
-Tablet must disintegrate in the gastro-intestinal (GI) tract and the drug then enter solution

Question 7

Capsules

Answer 7

-Drug in loose powder form is held within a 2-piece hard-shelled gelatin (usually) capsule
-Capsule shell quickly dissolves in the stomach and releases the drug
-Liquids / emulsions / pastes may be incorporated in 1-piece soft gelatin capsules

Question 8

Powders and granules

Answer 8

Typically mixed with water prior to taking
–> “Bulk” or “single-dose”

Question 9

Solutions

Answer 9

->Single phase systems
-Drug and other excipients are completely dissolved, i.e. as
a molecular dispersion, in a liquid (solvent)
-Faster acting than an equivalent tablet formulation-disintegration and dissolution steps are absent

Question 10

Suspensions

Answer 10

-Drug and/or other excipients remain as solid particles
dispersed in the “vehicle”
-Usually employ a suspending (thickening) agent to keep the particles dispersed

Question 11

Emulsions

Answer 11

-Dispersions of (at least) two immiscible or partially miscible liquids
-Medicinal oils, supplements,
lipophilic drugs

Question 12

Rectal and vaginal dosage forms

Answer 12

-Suppositories
-Enemas
-Foams
-Pessaries
-Vaginal creams and gels

Question 13

Suppositories

Answer 13

-Drug is incorporated into a water-soluble/dispersible base or a base which melts at body temperature
-Once inserted the drug will be released to exert a local or (sometimes) systemic effect

Question 14

Enemas

Answer 14

-Liquid preparations formulated for rectal delivery

Question 15

Foams

Answer 15

-Two-phase system administered from a pressurised container
-Drug dissolved in the liquid phase

Question 16

Pessaries

Answer 16

-Vaginal tablets, suppositories or capsules

Question 17

Topical and transdermal dosage forms

Answer 17

-Creams
-Ointments
-Gels
-Pastes / sprays / lotions / foams
-Transdermal therapeutic systems (patches)

Question 18

Creams

Answer 18

-Semi-solid emulsion preparations usually applied topically to the skin, but
formulated for other delivery routes
-May contain a drug or sometimes the cream “base” has a therapeutic effect

Question 19

Ointments

Answer 19

-Single-phase semi-solid base in which a drug can be dispersed
-Have excellent emollient properties

Question 20

Gels

Answer 20

-Single-phase semi-solid preparations, usually aqueous in nature

Question 21

Transdermal therapeutic systems (patches)

Answer 21

-Applied to the skin but usually for a systemic effect

Question 22

Parenteral dosage forms

Answer 22

Drug (or source of calories/ nutrients/ hydration) administered via a hollow metal needle
-Injections
-Infusions

Question 23

Injections

Answer 23

-Sterile liquid preparation drawn up and injected from a vial, ampoule or pre-filled syringe
-Typically IV, IM or SC, but many other routes
-Can utilise a syringe driver (or pump)

Question 24

Infusions

Answer 24

For delivery of larger volumes IV
-Source of calories/ nutrients/ hydration but drugs can also be added
-Can be solutions or emulsions, e.g. Intralipid®

Question 25

Pulmonary drug delivery systems

Answer 25

-Inhalers
-Nebulisers
-Electronic cigarettes

Question 26

Inhalers

Answer 26

-Large variety of different types of inhaler devices
-Pressurised metered-dose inhalers (pMDIs)
-Dry powder inhalers
Drugs are typically delivered for a local effect, e.g. salbutamol,
beclomethasone, but can also be given for a system effect

Question 27

Nebulisers

Answer 27

-Convert liquids to aerosols (dispersion of a liquid or a solid in a gas)
-Useful for delivering larger doses of drug

Question 28

Other common dosage forms

Answer 28

Question 29

Advanced dosage forms and technologies

Answer 29

-Needle-free technology, e.g. jet injection systems and
microneedles
-Implantable delivery systems
-Nanotechnology
-Cell-based therapies