however, they are less likely to be effective in conditions requiring
deep penetration to reach the site of pain, such as hip pain.
onsider the purpose of the skin—to keep things out of
our body and protect our systemic circulation. Not every
drug is suitable for topical or transdermal administration.
No matter how creative we get with dosage formulations,
the drug must still pass through the skin to work. This is
why not every medication can be compounded into a cream, slathered on, and expected to work. Medications that are likely to favor
topical use are usually lipid soluble with molecules small enough to
be absorbed.
An important distinction between topical and transdermal analgesics
is their location of action and method of absorption. To