Pharmaceutical Sciences Flashcards

What is a controlled-release formulation and what are its advantages?

Answer: A dosage form designed to release drug slowly over time, maintaining therapeutic levels with fewer daily doses

Controlled-release (CR/SR/XR) formulations release drug gradually to maintain steady plasma levels, reduce dosing frequency (improving compliance), minimize peak-trough fluctuations (reducing side effects), and provide sustained therapeutic effect. They must NOT be crushed or chewed.

What is the role of excipients in pharmaceutical formulations?

Answer: Inactive ingredients that aid in drug stability, absorption, appearance, taste, and manufacturing — such as binders, fillers, and preservatives

Excipients serve critical functions: binders (hold tablets together), fillers (provide bulk), disintegrants (help tablet break apart), lubricants (aid manufacturing), coatings (protect from moisture/light), preservatives (prevent microbial growth), and flavoring agents. Some patients may have excipient allergies (e.g., lactose, gluten).

What is pharmacovigilance and why is it important in Saudi Arabia?

Answer: The science of monitoring, detecting, assessing, and preventing adverse drug reactions post-marketing

Pharmacovigilance monitors drug safety after market approval. SFDA's National Pharmacovigilance Center (NPC) collects adverse drug reaction (ADR) reports from healthcare professionals. Saudi pharmacists have a legal obligation to report ADRs and medication errors to SFDA.

What is the Henderson-Hasselbalch equation used for in pharmacy?

Answer: Predicting the ionization state of drugs at different pH values, affecting absorption and distribution

The Henderson-Hasselbalch equation (pH = pKa + log [A-]/[HA]) predicts drug ionization at different pH levels. Un-ionized drugs cross membranes better. Weak acids absorb better in acidic environments (stomach), while weak bases absorb better in alkaline environments (intestine).

What is the significance of drug polymorphism in pharmaceutical manufacturing?

Answer: Different crystal forms of the same drug can have different solubility, stability, and bioavailability, affecting therapeutic efficacy

Polymorphism means a drug substance can exist in multiple crystal forms with different physical properties. Different polymorphs may have different solubility (affecting absorption), melting points (affecting stability), and dissolution rates (affecting bioavailability). Manufacturing must control polymorphic form.

What is the role of the SFDA in regulating pharmaceutical products in Saudi Arabia?

Answer: SFDA registers, evaluates, and monitors the safety, efficacy, and quality of all pharmaceutical products marketed in Saudi Arabia

The Saudi Food and Drug Authority (SFDA) is responsible for: drug registration and market authorization, manufacturing facility inspection (GMP compliance), post-marketing surveillance, pharmacovigilance, controlled substance regulation, and ensuring drug quality throughout the supply chain.