What are topical steroids and how do they work?

Topical steroids are creams, ointments and lotions which contain steroid drugs. Topical steroids work by reducing inflammation in the skin. They are used for various skin conditions, such as atopic eczema. Unlike many other creams and ointments, it is important to get the dose right when using topical steroids. This is why a standard measure is often used - the fingertip unit (FTU).

See separate leaflet called 'Topical Steroids for Eczema' for more information.

Fingertip units

One FTU is the amount of topical steroid that is squeezed out from a standard tube along an adult's fingertip. (This assumes the tube has a standard 5 mm nozzle.) A fingertip is from the very end of the finger to the first crease in the finger. One FTU is enough to treat an area of skin twice the size of the flat of an adult's hand with the fingers together.

Two FTUs are about the same as 1 g of topical steroid. Therefore, for example, say you treat an area of skin the size of eight adult hands. You will need four FTUs for each dose. (This is 2 g per dose. If the dose is once a day, then a 30 g tube should last for about 15 days of treatment.)

The following are further examples:

Fingertip units and children

An FTU of cream or ointment is measured on an adult index finger before being rubbed on to a child. Again, one FTU is used to treat an area of skin on a child, equivalent to twice the size of the flat of an adult's hand with the fingers together. You can gauge the amount of topical steroid to use by using your (adult) hand to measure the amount of skin affected on the child. From this you can work out the amount of topical steroid to use.

The following gives a rough guide:

For a 3-6 month-old child:

• Entire face and neck - 1 FTU.
• An entire arm and hand - 1 FTU.
• An entire leg and foot - 1.5 FTUs.
• The entire front of chest and abdomen - 1 FTU.
• The entire back including buttocks - 1.5 FTUs.

For a 1-2 year-old child:

• Entire face and neck - 1.5 FTUs.
• An entire arm and hand - 1.5 FTUs.
• An entire leg and foot - 2 FTUs.
• The entire front of chest and abdomen - 2 FTUs.
• The entire back including buttocks - 3 FTUs.

For a 3-5 year-old child:

• Entire face and neck - 1.5 FTUs.
• An entire arm and hand - 2 FTUs.
• An entire leg and foot - 3 FTUs.
• The entire front of chest and abdomen - 3 FTUs.
• The entire back including buttocks - 3.5 FTUs.

For a 6-10 year-old child:

• Entire face and neck - 2 FTUs.
• An entire arm and hand - 2.5 FTUs.
• An entire leg and foot - 4.5 FTUs.
• The entire front of chest and abdomen - 3.5 FTUs.
• The entire back including buttocks - 5 FTUs.

Further help and information

National Eczema Society

Hill House, Highgate Hill, London, N19 5NA
Tel (Helpline): 0800 089 1122 Web: www.eczema.org

References

• Long CC, Finlay AY; The finger-tip unit--a new practical measure. Clin Exp Dermatol. 1991 Nov;16(6):444-7. [abstract]
• Long CC, Mills CM, Finlay AY; A practical guide to topical therapy in children. Br J Dermatol. 1998 Feb;138(2):293-6. [abstract]
• Corticosteroids - topical (skin), nose, and eyes, Prodigy (August 2010)
• Bewley A; Expert consensus: time for a change in the way we advise our patients to use Br J Dermatol. 2008 May;158(5):917-20. Epub 2008 Feb 22. [abstract]