Sulfur (spelled sulpher in Europe) is a yellow, non-metallic
natural element and one of the building blocks of life. Sulfur
and hormones that are necessary for a healthy skin. Sulfur is
also a major component of keratin present in the skin, hairs and
Because of its antifungal, antibacterial and keratolytic properties,
sulfur has been for a long time a well known traditional medication
for treating many skin problems including acne. It is also a good
exfoliant for removing dead cells from the skin surface and helps
to control oil production. Faced with competition from other medications
the use of sulfur as a therapeutic agent in the treatment of acne
has lately come down. However, its efficacy and safety has been
well established and it still remains a good and reliable treatment
Mechanism of action
Sulfur is used alone and also in combination with compounds such
as sodium sulfacetamide and salicylic acid for treating acne.
How sulfur works as a medication is not well known. It is believed
that when sulfur is applied to the skin it reacts with a substance
called cysteine present in the skin and produces hydrogen sulfide.
Hydrogen sulfide breaks down keratin, resulting in a process called
keratolytic activity. The application of sulfur on the skin also
produces pentathonic acid which is toxic to fungus giving sulfur
its antifungal property. Its bacterial property is demonstrated
by the fact that sulfur has an inhibitory effect on propionibacterium
A study was done to compare the effectiveness of sulfur 10% cream
with systemic tetracycline. At the end of the study the only difference
found was in the number of papules and pustules. The sulfur cream
achieved a greater reduction in the number of inflamed lesions.
Also there was no difference in the relapse rate within 6 months.
Compared to other medications such as oral antibiotics, tretinoins,
antimicrobials and retinoids, sulfur produces very mild side effects
at the application site.
Sulfur is well absorbed by the body system. This was well demonstrated
in a study where sulfur was detected in the epidermis two hours
and throughout the skin within eight hours of application. Twenty
four hours after application no sulfur could be detected in the
skin. Such systemic absorption was demonstrated when 25% sulfur
ointment was applied to abraded animal skin. However, no such
absorption took place when sulfur was applied to healthy animal
Earlier studies had reported that sulfur was comedogenic on rabbit
ears and the human back. This issue was reexamined recently in
a study which involved application of a 5% test solutions of sulfur
on comedone free skins of healthy subjects with or without acne.
These applications were made three times per week for six weeks.
At the end of the study it was found that there was no correlation
between comedone developments and the presence or absence of sulfur
in the formulation applied.
Sulfur with sodium sulfacetamide
Sodium sulfacetamide has antibacterial properties. It inhibits
the action of paraaminobenzoic acid which causes bacterial growth.
It is also effective in suppressing the growth of propionibacterium
acne. What makes sodium sulfacetamide particularly attractive
is its effectiveness combined with the absence of any major side
effects. The response to treatment is consistent and it’s
cosmetically appealing formulation gets long term compliance of
The combination of sulfur and sodium sulfacetamide has been shown
as an effective therapy for acne lesions without excessive erythema.
Clinical trials, conducted with sulfur 5% and sodium sulfacetamide
10% formulations, were found to be quite effective in reducing
the number of comedones and inflammatory lesions. Almost 70 to
80% reduction was observed for both total number of lesions and
the inflamed lesions. The side effects such as dryness and itching
were rare, short lived and mild.
Formulations of sulfur and sodium sulfacetamide are available
as lotions, topical suspensions and cleansers.
The efficacy of sulfur therapy compared to other treatments is
well established. From the point of view of safety, considering
its mild and very transient side effects, it should undoubtedly
be a preferred treatment in many cases. Although the use of sulfur
and its compounds in acne treatment has declined, it still remains
a good treatment option.