a. General. Itching (pruritus) routinely accompanies many skin disorders.
Itching may be a symptom of a disease which affects the person's entire system; in liver
damage, for example, circulating bile salts cause itching all over the body. Persons
suffering from allergic reactions, blood disorders, and various psychologic disturbances
frequently experience itching. There are some simple antipruritics (agents which give
relief to itching, burning, pain) to help the patient avoid scratching and possibly causing
a secondary bacterial infection. Hot baths, heavy bed clothing, and rubbing of the skin
should be avoided because heat will cause the capillaries to get bigger in turn
increasing the itching feeling.
b. Local Anesthetics. Local anesthetics can be applied to a rather small area
and act to block or interfere with itching, burning, or pain by interfering with those
sensations. Here are three local anesthetics:
(1) Dibucaine. Dibucaine is a potent, toxic, long-acting local anesthetic
used in ointments for relief of pain. About 15 times as potent and toxic as procaine (a
mild medication), its anesthetic action lasts about three times as long as procaine.
(2) Benzocaine. This medication is also a local anesthetic, but benzocaine
is available in sprays, powders, and creams. Because it does not mix well with water,
benzocaine is absorbed into the skin slowly and is not toxic. The medication can be
applied directly to an open wound or ulcerated surface and will stay in place doing its
work of relieving pain for a long time.
(3) Lidocaine. Lidocaine is available in jelly form. This drug has a faster,
more intense, and longer lasting effect (relief of pruritus) than an equal concentration of
c. Phenol One Percent. Phenol is a substance obtained from coal and used as
an anesthetic and disinfectant. Phenol is often combined with other substances
because its anesthetic property will stop itching and also act as a disinfectant. A one to
five percent solution of cresol that contains phenol is sometimes used to disinfect skin.
The compound Resorcinol (one percent phenol) is used to treat skin diseases such as
eczema, seborrhea of the scalp, ringworm, and psoriasis.
d. Menthol/Camphor. Menthol provides a sensation of coolness by acting on
the skin's receptors. The concentration used should be one-tenth percent to one-
twenty-fifth percent. Camphor in a concentration of 0.5 percent to one percent provides
a sensation of coolness on the skin by evaporation. Both menthol and camphor in
medications are soothing to the skin.