B.Pharm 1st Semester General Pharmacy Unit 2 Important Questions

General Pharmacy Unit 2 introduces important concepts in pharmaceutical calculations, dosage design, and the basic principles of pharmaceutical formulations. For B.Pharm 1st Semester students, understanding these topics helps build the foundation for calculating doses, preparing appropriate formulations, and understanding how medicines are administered safely.

Important topics include the metric system of weights and measures, the alligation method, proof spirit calculations, isotonic solutions, posology, pediatric dose calculation methods, and the classification of dosage forms. Students should also understand the difference between Active Pharmaceutical Ingredients (APIs) and excipients, the functions of common excipients, and the importance of dosage form stability.

This article covers topic-wise important questions and answers for revision. Students can use these questions to revise definitions, explain key concepts, compare pharmaceutical terms, and prepare for descriptive or short-answer questions. Refer to your university's prescribed syllabus and class notes to confirm the topics required for your examination.

B.Pharm 1st Semester General Pharmacy Unit 2 Important Questions

1. Pharmaceutical Calculations, Weights and Measures

Q1. What are pharmaceutical calculations, and why are they important?

Pharmaceutical calculations involve mathematical operations used in preparing, dispensing, and administering medicines. They help determine quantities, concentrations, proportions, and appropriate doses. Accurate calculations are essential for maintaining the quality of pharmaceutical preparations and supporting patient safety.

Q2. What is the metric system in pharmacy?

The metric system is a decimal-based system of measurement used to express quantities such as mass, volume, and length. It uses standard units and multiples or submultiples of ten, making conversions and pharmaceutical calculations more systematic.

Q3. Differentiate between the metric, Avoirdupois, and Apothecaries systems.

• Metric system: A decimal-based system used for standardised measurements.

• Avoirdupois system: A traditional system of weights historically used for general commercial measurements.

• Apothecaries system: A traditional system of weights and measures associated with pharmacy and medicinal preparations.

Modern pharmaceutical calculations commonly use metric units.

Q4. Why are conversions between different systems of measurement important in pharmacy?

Conversions help pharmacists express quantities in the required units and avoid errors when interpreting measurements or calculating ingredient quantities. Students should practise the conversion factors prescribed in their course material.

2. Alligation Method

Q5. What is the alligation method in pharmaceutical calculations?

Alligation is a mathematical method used to calculate the proportions in which two or more preparations of different strengths can be mixed to obtain a desired intermediate strength.

Q6. Explain the alligation or criss-cross method.

The alligation method can be represented using a criss-cross or zigzag diagram:

1. Write the higher and lower concentrations on the left side.

2. Write the desired final concentration between them.

3. Subtract the desired concentration diagonally from the higher and lower concentrations.

4. Use the resulting differences as the proportionate parts of the respective preparations.

5. Simplify the ratio and calculate the quantities required for the final mixture.

The desired concentration must lie between the concentrations being mixed when using the basic two-component alligation method.

Q7. What is the main application of alligation in pharmacy?

Alligation helps determine the quantities of preparations with different strengths that must be mixed to obtain a required concentration. It is useful in pharmaceutical compounding and concentration-related calculations.

3. Proof Spirit Calculations

Q8. What is proof spirit?

Proof spirit is a reference standard used to express the strength of alcohol in a preparation. According to the supplied study material, Indian proof spirit contains 57.1% v/v absolute alcohol.

Q9. What is the difference between Over-Proof and Under-Proof alcohol?

• Over-Proof (O.P.): Alcohol strength is greater than proof spirit strength.

• Under-Proof (U.P.): Alcohol strength is lower than proof spirit strength.

In the proof-degree calculation described in the study material, a positive result indicates Over-Proof and a negative result indicates Under-Proof.

Q10. Why are proof spirit calculations important in pharmacy?

These calculations help express and interpret alcohol concentration relative to the recognised proof spirit standard. Students should practise converting alcohol strength and solving proof-degree problems using the formula taught in their course.

4. Isotonic Solutions and Tonicity Adjustment

Q11. What is an isotonic solution?

An isotonic solution has approximately the same effective osmotic pressure as the biological fluid with which it is compared. Maintaining suitable tonicity is particularly important for preparations intended for sensitive tissues, such as ophthalmic preparations.

Q12. What is the significance of isotonicity in pharmaceutical preparations?

Appropriate tonicity helps reduce undesirable osmotic effects on cells and tissues. A solution that differs significantly in tonicity from the surrounding biological fluid may cause cells to swell or shrink, depending on the direction of water movement.

Q13. What is the standard freezing point depression of blood plasma used in isotonicity calculations?

The reference value commonly used in pharmaceutical calculations is approximately −0.52°C.

Q14. Explain the freezing point depression method of adjusting tonicity.

The freezing point depression method uses the relationship between solute concentration and the lowering of a solution's freezing point. The freezing point depression of the preparation is compared with the reference value for blood plasma, and the required quantity of a suitable tonicity-adjusting agent is calculated.

Q15. What is the molecular concentration method of adjusting tonicity?

The molecular concentration method estimates the contribution of dissolved substances to the solution's osmotic concentration. Calculations consider factors such as molecular weight and the dissociation of solutes in solution.

Q16. Which reference concentrations are mentioned for isotonic solutions in the supplied study material?

The supplied material lists:

• Sodium chloride: 0.9% w/v

• Boric acid: 1.8% w/v

Students should use the reference values and calculation conventions specified in their prescribed textbook or course notes when solving numerical problems.

5. Posology and Factors Affecting Drug Dosage

Q17. What is posology?

Posology is the branch of pharmaceutical science concerned with the determination of drug doses. It considers patient-related factors and the characteristics of the medicine when determining an appropriate dose.

Q18. What are the major factors influencing drug dosage?

Important factors include:

• Age: Drug handling and physiological functions vary between infants, children, adults, and older people.

• Body weight: Weight can influence dose calculations and drug distribution.

• Body surface area (BSA): BSA is used in certain dose calculations, particularly when an appropriate dosing protocol specifies it.

• Physiological condition: The patient's overall condition may affect dose requirements.

• Individual drug characteristics: The medicine's properties and recommended dosing instructions also influence the dose.

Actual doses should always follow an appropriate prescribing or dosing protocol rather than being estimated solely from age or weight.

Q19. Why is body surface area used in dose calculation?

Body surface area provides a measure of body size that can be used in certain dosing calculations. It may be preferred in specific clinical contexts where the relevant dosing protocol uses BSA rather than age or body weight alone.

6. Pediatric Dose Calculation Methods

Q20. Why may pediatric doses differ from adult doses?

Children differ from adults in body size, organ development, and the way medicines are absorbed, distributed, metabolised, and eliminated. Therefore, pediatric doses may require individual calculation based on the medicine's approved dosing instructions and relevant patient factors.

Q21. Name the age-based formulas mentioned for pediatric dose calculation.

The supplied material lists the following formulas:

• Young's formula

• Dilling's formula

• Fried's formula

• Bastedo's formula

Students should learn the formula, age range, variables, and worked examples provided in their prescribed course material.

Q22. Which formula is associated with body-weight-based pediatric dose calculation in the supplied material?

Clarke's formula is listed as a method for calculating a pediatric dose using the child's weight relative to a standard adult body weight.

Q23. How is body surface area used for pediatric dose calculation?

A BSA-based calculation relates the child's body surface area to the reference adult body surface area used in the relevant dosing rule. The exact formula and values must be taken from the prescribed textbook or dosing reference.

Important: These formulas are study topics, not substitutes for current clinical dosing guidance. A child's actual medicine dose must be determined using an appropriate, medicine-specific clinical reference.

7. Dosage Forms and Their Classification

Q24. What is a dosage form?

A dosage form is the physical form in which a medicine is prepared for administration. It contains the active pharmaceutical ingredient along with any required excipients and is designed to support appropriate delivery of the medicine.

Q25. Classify dosage forms according to their physical form.

The classification may vary slightly according to the terminology used in the prescribed textbook.

Q26. How are dosage forms classified according to the route of administration?

Dosage forms may be classified by the route through which a medicine is administered, including:

• Oral

• Parenteral

• Topical

• Rectal

The choice of route depends on the medicine, intended therapeutic effect, patient requirements, and formulation characteristics.

Q27. Why are different dosage forms developed for medicines?

Different dosage forms help deliver medicines through suitable routes and support requirements such as dose accuracy, ease of administration, stability, patient acceptability, and the intended release or delivery characteristics.

8. Active Pharmaceutical Ingredients and Excipients

Q28. What is an Active Pharmaceutical Ingredient (API)?

An Active Pharmaceutical Ingredient is the substance responsible for the intended pharmacological or therapeutic action of a medicine.

Q29. What is a pharmaceutical excipient?

An excipient is an ingredient included in a pharmaceutical formulation alongside the API to support functions such as manufacturing, stability, delivery, appearance, or patient acceptability. Excipients are not necessarily pharmacologically inactive in every context, so their suitability and safety must be evaluated.

Q30. Differentiate between APIs and excipients.

Q31. What are the ideal characteristics of pharmaceutical excipients?

Suitable excipients should meet the required quality and safety standards, be compatible with the API and other formulation ingredients, and perform their intended function. Their stability and suitability depend on the formulation and route of administration.

9. Functional Categories of Pharmaceutical Excipients

Q32. What are disintegrants?

Disintegrants are excipients that help a tablet break apart after administration, allowing the formulation to disperse into smaller particles.

Q33. What are binders?

Binders provide cohesion between powder particles and help form granules or maintain the integrity of tablets during manufacturing.

Q34. What is the function of lubricants in tablet manufacturing?

Lubricants reduce friction between the formulation and manufacturing equipment during processes such as tablet compression and ejection.

Q35. Explain the functions of flavouring agents, colouring agents, and sweetening agents.

• Flavouring agents: Improve flavour and help make medicines more acceptable to patients.

• Colouring agents: Provide colour for appearance or identification.

• Sweetening agents: Improve palatability, particularly in formulations where taste may affect acceptance.

Q36. What are the functions of buffers and antioxidants in pharmaceutical formulations?

• Buffers: Help maintain a formulation's pH within the required range.

• Antioxidants: Help limit oxidation of susceptible formulation ingredients.

The selection of each excipient depends on its compatibility, safety, concentration, and intended function.

10. Dosage Form Stability

Q37. What is pharmaceutical stability?

Pharmaceutical stability is the ability of a medicine to maintain its specified quality characteristics throughout its shelf life when stored under the recommended conditions.

Q38. What are the main types of pharmaceutical stability?

Stability may be evaluated in several ways:

• Chemical stability: The medicine maintains its required chemical composition and potency.

• Physical stability: The product retains acceptable physical properties, such as appearance and uniformity.

• Microbiological stability: The product meets applicable microbiological quality requirements.

• Therapeutic stability: The product continues to meet the required performance and therapeutic quality specifications.

• Toxicological stability: Degradation or other changes do not cause the product to exceed applicable safety limits.

Q39. Why is stability testing important?

Stability testing helps establish how a medicine's quality changes over time under specified storage conditions. The results support shelf-life assignment, expiry dating, packaging decisions, and storage recommendations.

Q40. What factors can affect the stability of a dosage form?

Depending on the formulation, stability may be affected by temperature, light, moisture, oxygen, pH, interactions between ingredients, packaging, and microbial contamination. Suitable formulation design and storage conditions help maintain product quality.

Quick Revision: Important Topics to Prepare

Before the examination, revise the following areas and practise the related questions from your course notes.