December 4, 2007
Tetracyclines - The Workhorses In Oral Acne Therapy
The tetracyclines are the workhorses in oral acne therapy. They're the first-line oral antibiotic drugs of choice in the management of moderate to severe acne.
The tetracycline preparations inhibit the growth of P. acnes by going right to your sebaceous glands to attack the bacteria. They're bacteriostatic antibiotics, which means that they inhibit the growth of bacteria rather than kill them. In addition, they have an anti-inflammatory action that is equally important in the treatment of patients with papules and pustules.
There are three types of tetracyclines:
- Plain (generic) tetracycline
- Minocycline
- Doxycycline
Improvement of acne is usually noticeable in a matter of a few weeks or less with all of these tetracyclines. This response varies and depends on the severity of your acne; however, you may see the papules and pustules begin to flatten and disappear, and new ones should stop popping up. Tetracyclines may be tapered when this improvement persists. The decision about when and if to taper your dosage will be up to you and your doctor to decide. Often they have to be continued for long stretches of time — sometimes even for years.
Side Effects
Despite the low risk of side effects from tetracyclines, before taking the drugs, you should know a few things.
Because patients frequently use anti-acne oral antibiotics on a long-term basis (in some instances, for years), many people are understandably concerned about possible consequences. Studies have indicated that routine laboratory supervision of healthy young people given long-term tetracycline therapy isn't necessary. In a nutshell, in most cases, you don't need regular blood tests done while taking these antibiotics.
When treatment extends for more than one to two years, however, some dermatologists recommend periodically monitoring certain blood tests. This is particularly important if you have a history of liver, kidney, or an autoimmune disease. In such cases, you should get them checked more often.
One of the main side effects of tetracycline is staining the teeth of children. There are also risks to the teeth and bones of unborn babies and nursing children. You shouldn't take them if you are:
- A child under 10 years of age: The use of any of the tetracyclines during a child's tooth development (before the age of 10) may cause a permanent discoloration of the teeth.
- A woman who is breastfeeding or pregnant: If a tetracycline is taken during pregnancy or while breastfeeding, an infant's teeth can become discolored and there also may be a slowing down of the infant's bone growth. The discoloration of the baby teeth is due to calcification (hardening) of the teeth, which starts in the second trimester (after 12 weeks of pregnancy).
Tetracyclines may also temporarily stain the teeth of older patients, particularly those with orthodontic braces. When taking any one of the tetracyclines, you should practice good dental hygiene, including flossing.
Here are some other side effects that may occur when taking the tetracyclines:
- As with many other antibiotics, you may experience mild indigestion and abdominal upset. They can also cause more severe gastrointestinal irritation (inflammation of your esophagus or stomach).
- Rashes are uncommon, but when they appear, they can be severe.
- They can sometimes produce phototoxic reactions (an increased tendency to sunburn). This reaction is more likely to occur with doxycycline.
- If you have a history of vaginal yeast infections known as candidal vulvovaginitis, a broad-spectrum antibiotic such as a tetracycline or an erythromycin can permit such an infection to reappear. Candidal vulvovaginitis can also occur for the first time when using these antibiotics.
And use them cautiously if you have a personal or family history of lupus erythematosus (an autoimmune disease). And don't take them if you're allergic to any of the tetracyclines.
Tetracyclines also have the following very rare risks:
- Severe headaches due to increased pressure in the brain (intracranial hypertension) are seen very rarely. However, you can get "regular" headaches from the tetracyclines without developing this complication.
- A hivelike, hypersensitivity rash, which includes joint swelling.
- Drug-induced hepatitis with jaundice (yellowish discoloration of the whites of the eyes, skin, and mucous membranes), nausea, and dark urine.
If you develop any of the preceding symptoms, call your doctor immediately.
