Dispensing is the part of pharmacy where theory finally meets the bench. In PCT 212 – Dispensing Practical II, you (a 200 Level Pharm.D student at ABUAD) have to take a master formula and turn it into a preparation that is measured accurately and labelled correctly. This EverythingABUAD guide walks you through every dosage form on the second-semester syllabus and shows you where the marks are actually won and lost.
Here is the thing most students miss about PCT 212: the calculations are rarely what gets you. You lose marks confusing a diffusible solid with an indiffusible one, leaving off an auxiliary label, picking the wrong vehicle, or forgetting the poison cautions on a phenol preparation. So this guide does not just list formulae. It explains the reasoning behind each mixture, linctus, gargle, paint, drop and inhalation, then lets you test yourself on original practice questions with fully worked answers. The complete workbook is embedded in the interactive reader further down the page, free to read online or download.
- Course: PCT 212 – Dispensing Practical II
- College / Department: College of Pharmacy / Pharmacy
- Level / Semester: 200 Level, Second Semester
- Topics covered: Mixtures (Diffusible & Indiffusible Solids), Linctuses, Mouthwashes & Gargles, Paints, Nasal & Ear Drops, Inhalations, and Pharmaceutical Calculations & Theory
- Best for: Dispensing bench practice + continuous assessment + final exam revision
Topics Covered in PCT 212
1. Mixtures (Diffusible & Indiffusible Solids)
Oral mixtures are aqueous liquids dosed by the spoonful. Your main job is scaling a master formula (usually written per 100 mL) to the exact volume you need to prepare, always with a small excess to cover measuring loss. Then you decide whether a suspending agent is needed. Exam tip: know the difference between a diffusible solid (a light, fine powder like light magnesium carbonate that re-disperses on shaking, so no suspending agent) and an indiffusible solid (a dense powder like prepared chalk that cakes and needs tragacanth). Every mixture with a suspension gets a “Shake well before use” label.
2. Linctuses
A linctus is a thick, sweet, viscous syrup taken to soothe a cough. Because the vehicle is syrup, you prepare a little extra, since it clings to the measure and the mortar. Exam tip: be ready to explain why a linctus is sipped slowly and swallowed undiluted. The syrup coats and soothes the inflamed throat, a demulcent action that water would just wash away. You should also know why a diabetic codeine linctus swaps sugar syrup for a sorbitol/glycerol base while keeping the same sweetness and viscosity.
3. Mouthwashes & Gargles
These are thin, aqueous preparations that are diluted before use to rinse the mouth (mouthwash) or the throat (gargle). Exam tip: examiners love the “role of each ingredient” question, so have the four ready: an active antiseptic (e.g. liquefied phenol, potassium chlorate), an alkali or pH adjuster, a colourant/identifier (amaranth, patent blue V), and water as the vehicle. Know why oily or mucilaginous substances are avoided (they leave a clinging film and impair contact), and know the poison-handling cautions when phenol is present, including the “Not to be swallowed” label.
4. Paints
Paints are liquids applied to the skin or mucous membranes. Exam tip: learn to tell skin paints apart from throat paints. Skin paints use a volatile alcohol or acetone solvent that evaporates to leave an active film (e.g. Brilliant Green & Crystal Violet, Magenta/Castellani’s Paint). Throat paints are viscous and glycerol-based so they cling to moist mucosa (e.g. Compound Iodine Paint / Mandl’s Paint). Remember why they carry “Store in a cool place,” “For external use only,” and “Flammable,” and know the difference between an official and an unofficial preparation.
5. Nasal & Ear Drops
Both are small-volume drops, and the choice of vehicle is where the marks are. Exam tip: nasal drops use an aqueous vehicle (oily vehicles impair ciliary action and risk lipoid pneumonia if aspirated), and repeated use of a decongestant like ephedrine causes rebound congestion (rhinitis medicamentosa). For ear drops, glycerol is a viscous, hygroscopic vehicle that holds the drops in the canal, and you warm the drops to body temperature so they do not cause dizziness by stimulating the labyrinth.
6. Inhalations
Inhalations deliver volatile substances (menthol, eucalyptus oil) in steam. Exam tip: the classic question is the role of light magnesium carbonate. It acts as a dispersing agent or distributor: it adsorbs the volatile oils so they spread evenly through the water and are released steadily when added to hot water, instead of floating as a separate oily layer. Learn the patient directions too: “Add one teaspoonful to a pint of hot (not boiling) water and inhale the vapour.”
7. Pharmaceutical Calculations & Theory
This section sits under everything above: strength conversions (% w/v ↔ “1 in X”), single versus double-strength aromatic and chloroform waters, and dilution problems. Exam tip: practise converting between percentage strength and ratio strength both ways, and get the chloroform/aromatic-water rule down cold: single strength = double strength diluted with an equal volume of water, while concentrated waters are diluted one part to forty. Also learn the definitions of terms like analgesic, antipyretic, astringent, antiseptic, carminative, demulcent, rubefacient and sedative, each with an example ready to go.
Sample Practice Questions (With Answers)
Here are a few sample questions, written in our own words, with the reasoning spelled out so you understand the why and not just the answer:
Q1. You must prepare 160 mL of a chalk mixture from a master formula written per 100 mL. Is prepared chalk diffusible or indiffusible, and what is the role of the tragacanth?
Answer: Prepared (heavy) chalk is an indiffusible solid. It is dense, settles quickly and cakes, so an even dose cannot be poured without help. The tragacanth (2% w/v) is the suspending agent: it raises the viscosity of the vehicle so the chalk stays dispersed long enough for an accurate dose. Scale factor = 160 ÷ 100 = 1.6, so chalk 5 g × 1.6 = 8 g, and the container is labelled “Shake well before use.”
Q2. Why is a linctus sipped slowly and swallowed undiluted rather than washed down with water?
Answer: The thick syrup coats the inflamed pharyngeal mucosa and gives a prolonged local demulcent (soothing) effect. Diluting it or drinking water afterwards washes that film off the throat and loses the soothing action, which is the whole point of the dosage form.
Q3. Prepare 100 mL of potassium permanganate solution so that 10 mL diluted to 200 mL gives a 1 in 5000 gargle, using a 0.5% w/v stock. What strength must you dispense, and how much stock do you use?
Answer: “1 in 5000” = 0.02% w/v at the point of use. Diluting 10 mL up to 200 mL is a 20-fold dilution, so the dispensed solution must be 0.02% × 20 = 0.4% w/v. 100 mL of 0.4% contains 0.4 g; from a 0.5% stock (0.5 g/100 mL) you need (0.4 ÷ 0.5) × 100 = 80 mL of stock, made up to 100 mL with 20 mL of water.
Q4. In a menthol and eucalyptus inhalation, what is the role of the light magnesium carbonate?
Answer: It is a dispersing agent / distributor. It adsorbs the volatile oils (menthol and eucalyptus oil) so they are evenly distributed through the water; when a spoonful is added to hot water the oils are then released and volatilise steadily and uniformly, instead of floating on the surface as a separate oily layer.
How to Study PCT 212 Effectively
- Always start a dispensing question by finding the scale factor (volume to prepare ÷ master volume), then multiply every ingredient, and prepare a small excess for measuring loss.
- Build one reference table of diffusible vs indiffusible solids (behaviour on standing, need for a suspending agent, examples) and review it daily.
- Memorise the role of each ingredient in the standard formulae (active, vehicle, preservative, colourant, pH adjuster, suspending agent). This earns easy marks across every section.
- Drill the calculations both ways: % w/v ↔ “1 in X”, and single- vs double-strength waters, until they are automatic.
- Use this guide to understand each concept first, then use the workbook below to test recall under timed conditions.
Download the Full PCT 212 Practice Workbook
Ready to test yourself? Use the interactive reader below to work through our full set of practice questions with the complete worked answer key. You can read it directly on the page or download it for offline revision before your exam.
Frequently Asked Questions
Is this PCT 212 material free?
Yes. Every resource on EverythingABUAD is completely free for ABUAD students.
Does this cover the full PCT 212 syllabus?
It covers the core second-semester dispensing topics listed above: mixtures, linctuses, mouthwashes and gargles, paints, nasal and ear drops, inhalations, and the supporting calculations. Always cross-check against your lecturer's current course outline and the current pharmacopoeia.
Are these real past questions?
No. These are original self-test items written from scratch by the EverythingABUAD student team, modelled on the PCT 212 syllabus. They are not past papers and are not a prediction of any test.
About this resource: All summaries, explanations, study tips, and practice questions on this page were written, paraphrased, and adapted by the EverythingABUAD student team to support exam revision. This is an original study aid, not an official ABUAD document, and it is not a prediction of any future exam. Always cross-check quantities, doses and definitions against your lecturer's current course outline and the current pharmacopoeia.
