The Pharmacist OSCE Questions Flashcards
INTERNAL & EXTERNAL EMULSIONS
DENTINOX COLIC DROPS
Identify the excipient that is the emulsifying agent and explain how this particular emulsifying agent works?
The emulsifying agent is the carbomer and it swells when in contact with water to increase the viscosity of the continuous phase. This helps to keep the dispersed phase dispersed.
INTERNAL & EXTERNAL EMULSIONS
DENTINOX COLIC DROPS
Identify the 2 excipients used to improve the palatability of the product. What is the specific role of each one?
1 excipient used to improve the palatability of the product include sucrose which is used as a sweetener which helps to mask the taste of the drug
Another excipient is methyl parahydroxybenzoate E218, which is a colouring agent that can enhance the appearance and match the flavour
INTERNAL & EXTERNAL EMULSIONS
DENTINOX COLIC DROPS
Look at the ingredients, which do you think are the preservatives?
- Methyl parahydroxybenzoate,
- Ethyl parahydroxybenzoate
- Propyl parahydroxybenzoate
are the preservatives in this formulation
INTERNAL & EXTERNAL EMULSIONS
DENTINOX COLIC DROPS
What is the function of sodium hydroxide in the formulation, and how does it help the medicine to be tolerated by the patient?
It could be a acidity modifier to increase the pH level of the solution to reduce the risk of acid reflux
INTERNAL & EXTERNAL EMULSIONS
DENTINOX COLIC DROPS
When making an emulsion extemporaneously for oral administration, what additional safety label must be added to the dispensed label? Also, why is it important that the patient follows this instruction?
The additional safety label needed for internal emulsions is shake well before use. this is to ensure that the dispersed phase is dispersed well in the continuous phase
INTERNAL & EXTERNAL EMULSIONS
DENTINOX COLIC DROPS
What is the composition of the continuous phase of an oil in water emulsion to be taken orally, and why should the continuous phase contain a preservative?
The continuous phase is composed of water (purified in this medication).
The continuous phase must contain the preservative because water supports microbe growth and may feed on the emulsifying agent so a preservative is needed to prevent bacterial growth.
INTERNAL & EXTERNAL EMULSIONS
DERMAL 500 LOTION
This is an externally used oil-in-water emulsion, which takes the form of a lotion.
Describe 2 benefits to the patient of this type of product compared with using a semi-solid.
One benefit of using this formulation as opposed to a semi-solid is that it is less greasy than ointments which is more preferable and accepted by patients.
Another benefit is that it is less viscous than ointments so it is easier spread over large or hairy areas
INTERNAL & EXTERNAL EMULSIONS
DERMAL 500 LOTION
Which 2 excipients are being used as emulsifying agents in this product, and to which broad category of emulsifying agent do they belong?
??? benzalkonium chloride or macrogol cetostearyl ether, cetostearyl alcohol. these all belong to the group synthetic and semi-synthetic surfactants
INTERNAL & EXTERNAL EMULSIONS
DERMAL 500 LOTION
This product can be used as a soap substitute to clean the skin, which excipients in the product enable this use and how?
? macrogol as the surfactant can be used as an emulsifying agent
INTERNAL & EXTERNAL EMULSIONS
DERMAL 500 LOTION
What is “cracking” in reference to emulsions, and why is it important to avoid in medicines for patient use?
Cracking is when the dispersed phase and continuous phase is irreversibly separated and one phase is sat on top of the other
It is important to avoid in order to have an even distribution of the drug and have accurate dosing
INTERNAL & EXTERNAL EMULSIONS
DERMAL 500 LOTION
When making an oil-in-water emulsion by the dry gum method extemporaneously, why is it important to use a large mortar?
???
INTERNAL & EXTERNAL EMULSIONS
DERMAL 500 LOTION
When making an oil-in-water emulsion extemporaneously you would normally make a primary emulsion first before it is diluted to volume with more of the continuous phase. Why is this?
To ensure that all of the oil has been emulsified before diluting with more of the continuous phase
