NPC D.Pharm flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Bioavailability formula

Absolute bioavailability equals the oral AUC divided by the intravenous AUC, multiplied by the IV dose divided by the oral dose. It measures the fraction of an administered dose reaching systemic circulation unchanged.

Noyes–Whitney equation

Describes dissolution rate as proportional to surface area and the concentration gradient, and inversely proportional to diffusion layer thickness. Reducing particle size increases surface area and therefore dissolution rate.

First-order half-life

For first-order elimination, half-life equals 0.693 divided by the elimination rate constant. Half-life is independent of dose and remains constant as concentration falls.

HLB emulsifier rule

Emulsifiers with HLB 3 to 6 favor water-in-oil emulsions, while HLB 8 to 18 favor oil-in-water emulsions. Blends use the weight-weighted average HLB of components.

Tablet friability limit

A standard friability test uses a rotating drum; tablets should lose less than one percent of their weight. Higher loss indicates poor mechanical strength and risk of breakage during handling.

Competitive antagonist effect

A competitive antagonist binds reversibly at the agonist site and shifts the dose-response curve to the right. Maximal response remains achievable with enough agonist, unlike non-competitive antagonism.

Therapeutic index

Therapeutic index equals the toxic dose for 50 percent of subjects divided by the effective dose for 50 percent. A low index, as with digoxin or lithium, requires drug monitoring.

Volume of distribution

Volume of distribution equals the administered dose divided by the initial plasma concentration. A large value indicates extensive tissue distribution rather than plasma binding.

CYP3A4 inhibitors

Ketoconazole, clarithromycin, and grapefruit juice inhibit CYP3A4 and raise levels of substrates such as statins and calcium channel blockers. Rifampicin and carbamazepine act as inducers instead.

Aminoglycoside dosing rationale

Aminoglycosides kill bacteria concentration-dependently and show a post-antibiotic effect. Once-daily dosing achieves high peak levels for efficacy while allowing trough levels to fall, limiting nephrotoxicity.

Anaphylaxis first-line treatment

Intramuscular adrenaline 0.5 mg of 1:1000 solution into the anterolateral thigh is first-line for anaphylaxis. It is repeated every five minutes if needed, alongside airway support and fluids.

High-alert medications

Concentrated potassium chloride, insulin, heparin, opioids, and chemotherapy carry high harm risk when misused. They require independent double-checks, clear labelling, and segregated storage.

LASA drug risk

Look-alike, sound-alike medicines such as hydralazine and hydroxyzine cause selection errors. Tall-man lettering, physical separation, and barcode scanning reduce these dispensing mistakes.

Cytotoxic preparation cabinet

Cytotoxic drugs are prepared in a Class II biological safety cabinet using closed-system transfer devices, protective gowns, gloves, and eye protection. A spill kit must be immediately available.

Medication reconciliation

A structured comparison of the patient's current medicines with newly prescribed ones at admission, transfer, and discharge. It prevents unintended omissions, duplications, and dosing discrepancies.

Cold chain range

Most vaccines and insulin require storage between 2 and 8 degrees Celsius. Freezing damages adjuvanted vaccines and insulin, so refrigerator temperature must be logged daily.

Prescription-only medicine rule

A prescription-only medicine is dispensed only against a valid prescription from a registered prescriber. Schedule classification determines the level of control and record-keeping required.

Narcotic record requirements

Narcotic and psychotropic drugs require double-locked storage, separate registers, and retention of prescriptions. Records must be available for inspection by the licensing authority.

Spurious drug definition

A spurious drug is deliberately and fraudulently mislabelled with respect to identity, source, or manufacturer. It differs from an adulterated drug, which is contaminated or deficient in strength.

Pharmacist confidentiality duty

Patient health information obtained during dispensing is confidential and disclosed only with consent or where law requires. Breach is both an ethical violation and a professional misconduct.

Beer–Lambert law

Absorbance equals molar absorptivity times path length times concentration. The relationship is linear only for dilute solutions at a fixed wavelength and constant path length.

IR carbonyl absorption

A carbonyl group produces a strong absorption band near 1700 to 1750 inverse centimetres. This band helps identify esters, ketones, and carboxylic acids in an unknown compound.

HPLC resolution criterion

Resolution between two adjacent peaks should be at least 2 for reliable quantification. It depends on selectivity, column efficiency, and retention factor of the analytes.

Karl Fischer titration use

Karl Fischer titration specifically measures water content in a sample. It is not interchangeable with loss on drying, which also measures residual solvents and other volatiles.

Accelerated stability conditions

ICH accelerated stability testing uses 40 degrees Celsius at 75 percent relative humidity for six months. Long-term testing uses 25 degrees Celsius at 60 percent relative humidity.

Titration purity formula

Percent purity equals titre volume times normality times equivalent weight times 100, divided by sample weight. Units must be consistent, typically millilitres, milliequivalents, and milligrams.

Inhaler counselling steps

Shake the inhaler, exhale fully, seal lips, actuate at the start of inspiration, and hold the breath about ten seconds. Rinse the mouth after corticosteroid inhalers to prevent thrush.

ORS composition

Standard reduced-osmolarity oral rehydration solution contains sodium 75, glucose 75, potassium 20, citrate 10, and chloride 65 millimoles per litre. Glucose drives sodium and water absorption.

Hypoglycaemia management

Blood glucose below 70 milligrams per decilitre is treated with 15 grams of fast-acting carbohydrate. Recheck after 15 minutes and repeat if still low, then give a longer-acting snack.

HbA1c meaning

Glycated haemoglobin reflects average blood glucose over roughly two to three months. It is used for diabetes diagnosis and monitoring but is unreliable in anaemia and haemoglobinopathy.

Antibiotic adherence message

Patients should complete the full prescribed course, avoid sharing antibiotics, and never self-treat viral illness. Incomplete courses and misuse promote antimicrobial resistance in the community.

Self-medication red flags

Refer to a prescriber when symptoms are severe, persistent, or unexplained, or when the patient is pregnant, elderly, or on multiple medicines. Masking serious disease is the key risk.