DERMATOLOGICAL FORMULATIONS
EMOLLIENTS:
- Emollients = Moisturisers
- Function: creates an occlusive barrier on skin’s surface less water evaporating
from epidermis less dryness (enhances the skin’s natural ability to retain
moisture) – normally done by SEBUM
- Uses:
o Used alone to hydrate the skin in dry-skin conditions
o Used as a VEHICLE to deliver an API to skin (e.g. an antifungal)
The skin is naturally DRY & HYDROPHOBIC – thicker, oil-based vehicles have better
penetration into the skin (thus are MORE POTENT)
Similar principle to particle sizes in Clenil & Qvar – creams and ointments of the same
strength API may NOT always be interchangeable
CREAMS Vs OINTMENTS
Creams: Ointments:
- Water-based emulsions - Oil-based emulsions (like Vaseline)
- Easier to spread (better for larger areas) - Tougher to spread (best for small patches)
- Faster onset of action - Longer onset of action
- Shorter duration of action (more volatile) - Longer duration of action (less volatile)
- Has a drying effect – good for wet lesions - Less H2O loss – NOT used in wet-lesions
- Lower potency – suitable for all skin areas - Higher potency – NOT suitable for thin
- MORE cosmetically acceptable (does NOT skin e.g. face, eyelids, groin
leave greasy residue) - LESS cosmetically acceptable (very greasy)
OTHER TYPES OF VEHICLES:
- Lotions:
o Similar to creams but have a HIGHER H 2O content – even more volatile
o Useful in LARGE HAIRY SKIN – less likely to occlude follicles less folliculitis
o Have the WORST emollient properties (very volatile & hydrophilic)
o Are VERY DRYING – so very good for wet lesions
- Gels:
o Lie between ointments & creams in terms of occlusion
o Do NOT leave greasy residue, but not as potent as ointments
Emollient potency: Ointments > Gels > Creams > Lotions
CORRECT APPLICATION OF EMOLLIENTS:
- Always apply in DIRECTION OF HAIR GROWTH – helps to prevent blockage of hair
follicles less risk of FOLLICULITIS (do NOT rub the emollient in – just stroke it on)
- If decanting an emollient from a TUB or POT, always use a clean spoon/spatula to
remove from container – reduces risk of contaminating the emollient
, WHEN TO USE EMOLLIENTS:
- Can be used as OFTEN AS NEEDED – minimum TDS-QDS
- Apply AFTER washing/showering - this is when skin loses most sebum (& thus water)
- Always ensure to PAT-DRY skin before applying (for MAX effect)
- Apply BEFORE activities known to irritate the skin e.g. gardening
Some pts may benefit from using a cream throughout the DAY & an ointment at NIGHT
EXCIPIENTS & SENSITIVITIES:
- Although rare, some patients experience local HS reactions to some EXCIPIENTS:
o Beeswax (An emulsifier)
o Alcohols (maintain stability of emollient – keeps it homogenous)
o Parabens (preservatives)
o Fragrances
Always do a PATCH TEST before using a NEW product
OTHER HAZARDS ASSOCIATED WITH EMOLLIENTS:
- FIRE HAZARD: emollients can soak into clothes more flammable
- SLIP HAZARD: esp when used in shower/slippery surface (use anti-slip mat)
ISSUES WITH AQUEOUS CREAM (AC):
- AC is an emollient & can be used as BOTH a LEAVE-ON AND a SOAP SUBSTITUTE
- AC has a high content of sodium lauryl sulphate (SLS) – needed for stabilisation
- High SLS % local skin reactions e.g. burning, red, itchy skin (ESP IN CHILDREN)
- LESS likely to occur when used as a soap-substitute (less contact time w/ skin)
BARRIER PREPARATIONS
OVERVIEW:
- Barrier preparations: thick, WATERPROOF emollients which protect skin against
damage from bodily waste/fluids (i.e. they form a BARRIER on skin’s surface)
- INDICATIONS: (usually in areas prone to fluid exposure)
o Nappy rash (due to accumulation of faeces in nappies)
o Incontinence (same rationale as above)
o Used around stomas (as discharge/secretions can leak out onto skin)
o To heal pressure sores/bedsores (do NOT help in preventing bedsores)
NAPPY RASH:
- CAUSES:
o Not changing soiled nappies regularly enough
o Friction caused by ill-fitting nappies
o Irritation from topical products/wipes (usually fragranced)
- SYMPTOMS: red, inflamed, hot patches of skin around nappy areas (may blister)
EMOLLIENTS:
- Emollients = Moisturisers
- Function: creates an occlusive barrier on skin’s surface less water evaporating
from epidermis less dryness (enhances the skin’s natural ability to retain
moisture) – normally done by SEBUM
- Uses:
o Used alone to hydrate the skin in dry-skin conditions
o Used as a VEHICLE to deliver an API to skin (e.g. an antifungal)
The skin is naturally DRY & HYDROPHOBIC – thicker, oil-based vehicles have better
penetration into the skin (thus are MORE POTENT)
Similar principle to particle sizes in Clenil & Qvar – creams and ointments of the same
strength API may NOT always be interchangeable
CREAMS Vs OINTMENTS
Creams: Ointments:
- Water-based emulsions - Oil-based emulsions (like Vaseline)
- Easier to spread (better for larger areas) - Tougher to spread (best for small patches)
- Faster onset of action - Longer onset of action
- Shorter duration of action (more volatile) - Longer duration of action (less volatile)
- Has a drying effect – good for wet lesions - Less H2O loss – NOT used in wet-lesions
- Lower potency – suitable for all skin areas - Higher potency – NOT suitable for thin
- MORE cosmetically acceptable (does NOT skin e.g. face, eyelids, groin
leave greasy residue) - LESS cosmetically acceptable (very greasy)
OTHER TYPES OF VEHICLES:
- Lotions:
o Similar to creams but have a HIGHER H 2O content – even more volatile
o Useful in LARGE HAIRY SKIN – less likely to occlude follicles less folliculitis
o Have the WORST emollient properties (very volatile & hydrophilic)
o Are VERY DRYING – so very good for wet lesions
- Gels:
o Lie between ointments & creams in terms of occlusion
o Do NOT leave greasy residue, but not as potent as ointments
Emollient potency: Ointments > Gels > Creams > Lotions
CORRECT APPLICATION OF EMOLLIENTS:
- Always apply in DIRECTION OF HAIR GROWTH – helps to prevent blockage of hair
follicles less risk of FOLLICULITIS (do NOT rub the emollient in – just stroke it on)
- If decanting an emollient from a TUB or POT, always use a clean spoon/spatula to
remove from container – reduces risk of contaminating the emollient
, WHEN TO USE EMOLLIENTS:
- Can be used as OFTEN AS NEEDED – minimum TDS-QDS
- Apply AFTER washing/showering - this is when skin loses most sebum (& thus water)
- Always ensure to PAT-DRY skin before applying (for MAX effect)
- Apply BEFORE activities known to irritate the skin e.g. gardening
Some pts may benefit from using a cream throughout the DAY & an ointment at NIGHT
EXCIPIENTS & SENSITIVITIES:
- Although rare, some patients experience local HS reactions to some EXCIPIENTS:
o Beeswax (An emulsifier)
o Alcohols (maintain stability of emollient – keeps it homogenous)
o Parabens (preservatives)
o Fragrances
Always do a PATCH TEST before using a NEW product
OTHER HAZARDS ASSOCIATED WITH EMOLLIENTS:
- FIRE HAZARD: emollients can soak into clothes more flammable
- SLIP HAZARD: esp when used in shower/slippery surface (use anti-slip mat)
ISSUES WITH AQUEOUS CREAM (AC):
- AC is an emollient & can be used as BOTH a LEAVE-ON AND a SOAP SUBSTITUTE
- AC has a high content of sodium lauryl sulphate (SLS) – needed for stabilisation
- High SLS % local skin reactions e.g. burning, red, itchy skin (ESP IN CHILDREN)
- LESS likely to occur when used as a soap-substitute (less contact time w/ skin)
BARRIER PREPARATIONS
OVERVIEW:
- Barrier preparations: thick, WATERPROOF emollients which protect skin against
damage from bodily waste/fluids (i.e. they form a BARRIER on skin’s surface)
- INDICATIONS: (usually in areas prone to fluid exposure)
o Nappy rash (due to accumulation of faeces in nappies)
o Incontinence (same rationale as above)
o Used around stomas (as discharge/secretions can leak out onto skin)
o To heal pressure sores/bedsores (do NOT help in preventing bedsores)
NAPPY RASH:
- CAUSES:
o Not changing soiled nappies regularly enough
o Friction caused by ill-fitting nappies
o Irritation from topical products/wipes (usually fragranced)
- SYMPTOMS: red, inflamed, hot patches of skin around nappy areas (may blister)
