Breakouts

Should a major blemish suddenly appear, call your dermatologist. A cortisone injection will shrink it within 24 hours. Is your doctor AWOL? Arielle Kauvar, M.D., a cosmetic dermatologist in New York City, recommends Neutrogena's On-the-Spot Acne Patch; worn overnight, it visibly reduces any redness or swelling.

Under-eye circles

Consult your doctor to determine the best way to lighten them, says Dr. Kauvar. If pigmentation is causing the problem, bleaching creams can help, but even prescription-strength medicines take at least six weeks to work. A quicker fix—but considerably more expensive—is laser treatment; one visit alone can produce a 70 percent improvement, says Dr. Kauvar.

Cold sores

Always have a five-day course of oral antibiotics on hand for this recurring viral condition (pay attention to any localized tingling—a sign that a sore is on the way). Start taking the medication the moment you feel this sensation, and the sore may never emerge, says Kauvar. If it does, dry it out with over-the-counter Domeboro tablets or powder dissolved in water.

Sunburn

Lobster skin? Treat the condition like any acute burn, says Dr. Kauvar: Apply cold compresses, take aspirin or ibuprofen to relieve pain and reduce swelling, and smooth on a gentle moisturizer like Lubriderm Skin Therapy Moisturizing Lotion to help prevent peeling.

Sun spots

Fat freckles and beauty marks will fade quickly with in-office chemical peels, says Dr. Kauvar. Any irritation should clear within a week or two. For lighter discoloration, use acid-based toners and moisturizers that gradually lighten skin over several weeks. And always wear sun block. Editor's pick: Peter Thomas Roth's Glycolic Acid 10% Moisturizer.