RE-formulation

Question 1

Reformulation of dosage forms

Purpose

Answer 1

-Lack of appropriate dosage forms (majority of the drug products are available in liquid forms- CHILDREN)
NB- dose in kids is calculated by weight with liquid there is dose flexibility as opposed to tablets
-Improve patient compliance (e.g. patient suffering from stroke-swallowability, taste masking)
-Enhances product life cycle- enhanced patent
-To develop formulations with different release profiles (e.g. sustained and controlled release systems of carbamazepine this reducing dose frequency- good for patient compliance )
-Reduce cost of therapy

Question 2

reformulation of dosage forms

Answer 2

• Increasing demand for large number of licensed drug products to be reformed
• It is estimated that up to 70% of drug usage in paediatric patients is unlicensed
• Paediatric patients are treated with extemporaneous formulations which are known as specials
• A special formulation is developed either due to lack of drug product in oral liquid form which is suitable for administration to paediatric patients as it permits fractional dosing or for clinical conditions which require medicines which are SF or preservative free

Question 3

Case study 1

Answer 3

• Formulation of captopril oral solution (5mg/ml) Qty: 250ml
• Captopril is available as tablets (50mg)
• How many tablets: 25
• Therapeutic use: ACEI, ,lower BP
• How would you formulate the solution: crush tablets, add distilled water in portions and levigate (make into a paste). Make up the volume to 250ml in a clinical flask
• If solubility of captopril is only 2mg/ml- Look at co-solvents and suspension

Question 4

Case study 2

Answer 4

Formulation of simvastatin oral suspension (this suggests poor solubility)

• Simvastatin is available as tablets- 10,20,40
• Therapeutic use of simvastatin- lower ChE
• Crush tablets and add Suspending agent (xanthan gum, methyl cellulose) to form a pasteplace in distilled water
• What characterisation studies would you perform

Question 5

Case study 3 (ointment)

Answer 5

• Formulation of bethamethasone validate (0.1%) cream in white soft paraffin (10% w/w)- dispense 200g
• Write down the necessary calculations: 20g betnovate with 180g paraffin
• How would you formulate this product: weigh the ingredients and mix them in geometry proportions with a spatula on an ointment slab. Transfer the ointment into a plastic jar and seal

Question 6

Case study 4

Answer 6

Camphor 5%, eucalyptus 5%, menthol 5% in soft white Qty 500g

• Camphor- 25g
• Eucalyptus- 25g
• Menthol- 25g
• White soft paraffin- 425

Question 7

Case 5- GP ask for omeprazole oral liq formulation- 2mg/ml (solubility on 100mcg/ml). omeprazole comes as enteric coated tablets
Suggest suitable formulation. excipients for reformulation as an oral liquid

Answer 7

-Oral suspension
-Elixir (ethanol co-solvents)
-Must have a buffer at 3.5 (unstable with acid)
-Levigate with suspending agents (xanthan gum, methyl cellulose)
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