Pharmacology for Dentistry

Drugs used in Skin Disorders 451

sulfur for the treatment of acne vulgaris and
acne rosacea.

ANTIFUNGAL AGENTS

Detailed pharmacology of antifungal agents
(oral & topical) is discussed in detail in
chapter ‘Chemotherapeutic agents-
Antifungal agents’.

ANTIVIRAL AGENTS

Detailed pharmacology of acyclovir,
valacyclovir, penciclovir and famciclovir is
discussed in detail in chapter ‘Chemothera-
peutic agents- Antiviral agents’.

IMIQUIMOD

It is an immunomodulator agent used
locally in the treatment of external genital
perianal warts in adults.

Adverse effects include local inflamma-
tory reaction, erythema, pruritus etc.

STEROIDAL PREPARATIONS

Topical corticosteroids are used in the
treatment of inflammatory dermatoses. The
general pharmacology are discussed in
chapter ‘Glucocorticoids’.

ECTOPARASITICIDES

LINDANE

It is a gamma isomer of hexachlorocycl-
ohexane used as pediculicide and scabicide
in the form of lotion, shampoo and cream.

Adverse effects include neurotoxicity,
haematotoxicity and local irritation when it
comes in contact with eye and mucous
membrane.

CROTAMITON

It is scabicide, pediculocide and

antipruritic used in the form of lotion and

cream.

PERMETHRIN

It is neurotoxic to Pediculus humanus,

Pthirus pubis and Sarcoptes scabiei.

It is used in the form of cream. Adverse

effects include transient burning and

stinging.

Sulphur is used as scabicide and benzyl

benzoate is effective as pediculicide and

scabicide.

DEMELANIZING AGENTS

Hyperpigmentation is an aberration in

which dark spots on the skin, which often

make it cosmetically undesirable. This

benign condition is attributed to an

overproduction of melanin, a dark-coloured

pigment in the skin. The relative amount of

melanin as well as other skin pigments,

genetically determine an individual’s skin

colour. Thus, people with innately dark skin

have more melanin than people with lighter

skin colour. The production of melanin is

dependent upon the activity of the enzyme

tyrosinase. This enzyme is essential in

catalyzing the reaction that produces

melanin. Thus drugs that block tyrosinase,

inhibit the overproduction of melanin.

Post-inflammatory hyperpigmentation

is the most common cause of hyperpigmen-

tation, which occurs after irritation or in-

flammation of the skin for example after an

episode of acne. This type of hyperpigmen-

tation occurs more often in darker skinned