The strength of a steroid is not the only priority in establishing safe usage. Along with potency, one must be aware of how different body parts absorb the topical steroid.
The most sensitive areas on an individual are the eyelids, face, and genital area. These parts of the body are extremely sensitive to steroid use. Only mild topical steroids should be used on these areas* and for a very short period of time (Generally no more than 2 -4 weeks of topical steroid use). The least sensitive areas on an individual are the palms of the hands and soles of the feet. Steroid safety should still be used on these areas ***Note: For newborns, toddlers, and the elderly, the skin is extremely sensitive (brand new baby skin and thinning skin in elderly patients) so it is very important to exercise great care and maintenance while using topical steroids. These individuals are more susceptible to side effects.
Once area sensitivity is established, you can use the ‘fingertip rule‘ for topical steroid application. Certain areas of the body need different amounts of the topical steroid. By using the very tip of your finger (the very tip to your first knuckle), you can measure out how much each surface area you will need for each application.
One must also be aware that if your doctor prescribes a topical steroid for full body use, the body will be absorbing that much more of the steroid as opposed to just one appendage such as an elbow or the neck. This also increases the chance of side effects.
* in my opinion, topical steroids should never be used on the face due to how easily the steroid can be absorbed.
Preventable: Protecting Our Largest Organ 