Thursday, September 08, 2005

Ocular Rosacea Treatment Options

There are a variety of treatment options available for ocular rosacea, no one therapeutic regimen has been found effective in all cases, and many cases of ocular rosacea are recalcitrant to multiple therapies. Therefore, treatment always must be tailored to each individual, and various options must be explored until symptoms begin to respond favorably.
Lid hygiene: Hot compresses applied to the eyelid margins can help to liquefy the thick meibomian gland secretions and, thus, facilitate their expression. Mild, nonirritating cleaning solutions, such as dilute baby shampoo or commercially prepared eyelid scrubs, also can be applied to the eyelids to remove clogging debris. Additionally, light pressure applied to the eyelids can aid in gland expression.
Artificial tears: Because of the frequency of application, nonpreserved artificial tears are recommended for use. Tears should be applied liberally throughout the day, and, if necessary, a lubricating ointment may be used at night. This ointment may contain an antibiotic preparation.
Antibiotics (Patients with ocular rosacea who are asymptomatic and without worsening eye disease should not be placed on oral antibiotics.)
Tetracyclines (tetracycline, doxycycline, minocycline)
Tetracyclines represent the most common and most effective treatment regimen for rosacea. These drugs are believed to be effective not primarily as antibiotics but rather through a secondary effect that they exert on the meibomian glands. Tetracyclines decrease bacterial lipase, thereby altering the fatty acid composition of the meibomian gland secretions and improving their solubility. These medications also inhibit collagenase; therefore, they are effective in protecting the cornea from impending perforation secondary to inflammatory responses.
Adverse effects are predominantly gastrointestinal, including diarrhea and rarely pancreatitis and pseudomembranous colitis. More severe but much less common adverse effects include benign intracranial hypertension and renal tubular damage (Fanconi syndrome) from outdated medications. Additionally, tetracyclines cross the placenta and can cause permanent discoloration of teeth as well as retardation of fetal bone growth.
Tetracyclines generally are effective for rosacea in doses much lower than those given for antibiotic effect, and, once the disease has come under control, the dose may be tapered to a lower, suppressive dose and maintained indefinitely. Due to the chronic, relapsing nature of rosacea, the medication may be used chronically at suppressive doses or discontinued and restarted if and when symptoms recur.
Among this class of medications, tetracycline and doxycycline most commonly are used. The 2 medications are quite similar in their mechanism of action, side effect profile, and efficacy, but slight differences do exist. Tetracycline has a shorter half-life and, thus, is dosed 4 times per day, as opposed to doxycycline, which is given twice per day or once per day. Frucht-Pery et al reported a more rapid therapeutic response to tetracycline; however, no difference was found at 6 months. Additionally, the side effects profile is slightly more favorable for doxycycline.
Erythromycin can be taken orally for patients intolerant to, or too young for, tetracyclines. Erythromycin ointment applied to the lid margins once or twice daily can provide lubrication for the eye and reduce the bacterial overgrowth contributing to lid margin disease.
Clarithromycin has shown efficacy in treating rosacea. This compound exhibits anti-inflammatory effects as well as activity against H pylori. Torresani compared clarithromycin and doxycycline and found equivalent therapeutic responses and a milder side effect profile for clarithromycin.
Metronidazole
Metronidazole exhibits antimicrobial (antibacterial and antiparasitic), anti-inflammatory, and immunosuppressive properties and has been found effective against rosacea. Oral metronidazole has in fact been advocated as first-line therapy. Adverse effects include gastrointestinal irritation and a disulfiramlike action; thus, abstinence from alcohol is required.
Topical metronidazole is quite effective in treating skin lesions in rosacea. While not approved for ophthalmic use, in a pilot study, Barnhorst et al found the topical compound to be safe and effective in treating eyelid involvement in ocular rosacea.
Topical steroids can prove useful for short-term exacerbations of lid disease and management of inflammatory keratitis. However, steroids should be used cautiously and discontinued as soon as possible to prevent corneal melting.
Retinoids: Vitamin A derivatives, such as oral isotretinoin and topical tretinoin, have been found effective in reducing the inflammatory lesions in rosacea. This appears to be accomplished via the suppression of sebum production and a subsequent reduction in sebaceous follicle size. Additionally, tretinoin may help restore sun-damaged skin through the increased production of type 1 collagen in damaged regions. Both compounds actually can cause severe erythema and blepharoconjunctivitis, worsen telangiectasias, and lead to severe keratitis. Additionally, retinoids are extremely teratogenic and, thus, must never be used during pregnancy. Therefore, the use of retinoids commonly is reserved for cases in which multiple agents have failed.
Antiulcer therapy: H pylori plays an as yet undetermined role in rosacea, and some have advocated H pylori eradication in treatment of rosacea. Thus, in some cases of rosacea, antiulcer combination regimens, such as amoxicillin or clarithromycin, metronidazole, bismuth, and an H2 antagonist have been used with varying efficacy.