ints which usually mark the
lesions are probably due to accumulation of dirt, but may, as some
writers maintain, be due to the presence of pigment-granules resulting
from chemical change in the sebaceous matter.

#Is there any difficulty in the diagnosis of comedo?#

No. It can scarcely be confounded with milium, as in this latter disease
the lesion has no open outlet, no black point, and the contents cannot
be squeezed out.

#Give the prognosis of comedo.#

The result of treatment is usually favorable, although the disease is
often rebellious. Relapses are not uncommon.

#How would you treat a case of comedo?#

By systemic (if indicated) and local measures.

The constitutional treatment aims at correction or palliation of the
predisposing conditions, and the external applications have in view a
removal of the sebaceous plugs and stimulation of the glands and skin to
healthy action.

[Illustration: Fig. 9. Comedo Extractor.]

#Name the systemic remedies commonly employed.#

Cod-liver oil, iron, quinine, arsenic, nux vomica and other tonics;
ergot in those cases in which there is lack of muscular tone, salines
and aperient pills in constipation. The digestion is to be looked after
and the bowels kept regular; indigestible food of all kinds is to be
interdicted. Hygienic measures, such as general and local bathing, local
massage, calisthenics, and open-air exercise, are of service.

#Describe the local treatment.#

Steaming the face or prolonged applications of hot water; washing with
ordinary toilet soap and hot water, or, in sluggish cases, using
tincture of green soap (tinct. saponis viridis) instead of the toilet
soap; removal of the sebaceous plugs by mechanical means, such as
lateral pressure with the finger ends or perpendicular pressure with a
watch-key with rounded edges, or with an instrument specially contrived
for this purpose; and after these preliminary measures, which should be
carried out every night, a stimulating sulphur ointment or lotion, such
as employed in the treatment of acne (_q. v._), is to be thoroughly
applied. The following is valuable:--

[Rx] Zinci sulphatis,
Potassi sulphureti, . [=a][=a] ....... [dram]j-[dram]iv.
Alcoholi ............................. f[Oz]ss.
Aquae, ................. q.s. ad ...... f[Oz]iv. M.

Should slight scaliness or a mild degree of irritation of the skin be
brought about, active external treatment is to b