Introduction to formulations

Question 1

How do we classify dosage forms and give examples?

Answer 1

• Based on route of administration or physical forms (e.g. solid, liquid and semi solid)
• Oral, vaginal, transdermal, nasal

Question 2

Factors to consider when a drug is being formulated

Answer 2

• Target population (general, geriatric, paediatric, healthy, conscious?)
• Route of administration
• Formulation type, dose, regimen
• Stability/Shelf life
• Means of manufacture

Question 3

Describe what occurs in the pre-formulation stage

Answer 3

• Pre-formulation – investigation of key properties of the API
• Formulation – means of delivering the API
• • Physico –chemical properties, e.g.:
• Determination of molecular structure (Analytical techniques PM2PY3)
• Crystal form – crystalline, amorphous; polymorphic form (Crystals Lectures)
• Solubility (and dissolution) – all APIs must have (some) aqueous solubility for therapeutic effect
  (Liquid formulations, Prof Shankland’s Biopharm and Pharmacokinetics Lectures and others)
• Stability (T°, humidity, oxygen, light)
• Drug-additive interactions
• Organoleptic properties (related to taste, smell, sight, touch)
• Physico-mechanical properties:
• Powder properties (Powders and Tablets Lectures)
• particle size
• surface area
• powder flow and densities
• compression properties
• Wettability