Acne in its more severe form has the potential to scar and permanently
disfigure young adults, the resulting psychological and social
damage being more severe when the face is involved. Such inflammatory
acne has, therefore, to be immediately and properly treated. Various
systemic treatments may be the best options in such cases. Oral
antibiotic treatment is one of the available options.
Oral antibiotics treatment is the first choice when:
Acne is of a moderate to severe type.
- Acne is not cured by topical
- Acne covers a large part of the body, particularly
the chest back and shoulders.
Tetracycline, and its second generation derivatives minocycline
and doxycycline, are among the most common oral antibiotics
used in systemic treatment. These antibiotics suppress Propionibacterium
acnes growth and also have anti-inflammatory properties. They
can also reduce the number of comedones. The effectiveness of
these drugs depends on their ability to penetrate the micro
environment of the pilosebaceous follicles where the propionibacterium
resides. The more penetration the better is the efficacy of
the oral antibiotic. Clinical experience and data available
to date show that minocycline and doxycycline are more effective
Oral antibiotics are a long term therapy in acne, the normal
duration of treatment being 4 to 6 months. Therefore, before prescribing
these drugs, their reactions with drugs already being taken by
the patients should be considered. For women with acne, a combined
therapy of oral antibiotics and hormonal treatment, where oral
contraceptives are used, is recommended. The common view that
oral antibiotics reduce the efficacy of the oral contraceptives
is largely unfounded, since the failure rates of the contraceptives
with or without antibiotics is almost the same according to published
Tetracycline is a safe drug and generally healthy patients on
this drug need not be regularly monitored. It is often effective
in previously untreated cases of severe acne. Random trials have
shown 50% to 60% rate of improvement in inflammatory acne. Treatment
failures occur because of poor compliance, inadequate treatment
duration, folliculitis development, bacterial resistance or high
sebum secretion. It is one of the least expensive antibiotic drugs
which makes it a popular choice. The main disadvantage of tetracycline
is that it needs to be taken on an empty stomach since its absorption,
and therefore its effectiveness, is reduced by any intake of food.
Side effects of tetracycline are gastrointestinal problems, vaginal
candidiasis and photosensitivity. These drugs can also cause permanent
bone and teeth pigmentation in some cases. They are not recommended
for pregnant women and children below 12 years of age. A general
complaint is frequent abdominal problems.
Minocycline is the most frequently prescribed oral antibiotic
because the response to its use in treatment protocols is quicker.
This is so because its penetration of the pilosebaceous hair follicles
is better. But the view that it should be a first line of treatment
has few supporters. Unlike tetracycline, minocycline can be taken
with meals as food affects its absorption less. It is one of the
most expensive drugs which can be an issue in countries with public
state health care systems. Currently the view is that, though
minocycline is most effective in moderate acne, its effectiveness
compared to other treatments is yet to be determined.
Minocycline can cause headaches, vertigo, and hyperpigmentation
of the skin. It can also cause some allergic reactions, and very
rarely autoimmune disorders like autoimmune hepatitis, hypersensitivity
reactions like hepatitis and pneumonitis and also death due to
hepatoxicity and myocardial necrosis! Gastro intestinal problems
are much less compared to those caused by tetracycline because
minocycline is absorbed better when given orally. Patients on
minocycline should be checked every 3 to 4 months for liver function
and antinuclear factor in their blood.
Doxicycline can be taken with meals as this drug also penetrates
the pilosebaceous follicles as well as minocycline. Among the
three drugs, doxicycline is most likely to cause dose dependent
photosensitivity reactions. Doxicycline, like minocycline, causes
less gastrointestinal problems than tetracycline.
The use of doxicycline in lower doses in inflammatory acne has
been found to be not only effective, but also safe since side
effects are fewer and risk of developing bacterial resistance
is lower compared to tetracycline and minocycline. If further
studies confirm this benefit, it is likely that lower doses will
A disturbing development in recent years in antibiotic treatment
of acne has been a marked increase in bacterial resistance to
these drugs. Several studies have confirmed this trend. Therefore,
reducing bacterial resistance is now a primary aim in acne treatment.
However, compared to other antibiotics, such as erythromycin,
resistance is less common with tetracycline and doxicycline and
rare with minocycline. Some strategies adopted for reducing resistance
with oral antibiotics are; minimizing use of antibiotics, discontinuing
oral antibiotics when acne control is achieved, and prescribing
the same oral antibiotic for re-treatment.