If your skin problem does not improve within 2 to 4 weeks, or if it becomes worse, check with your doctor.

Inform your doctor right away if the area where you applied the medicine shows signs of increased irritation (e.g., redness, itching, burning, blistering, swelling, or oozing) because it could be an allergic reaction.

Nail problems treated with the topical solution form of PENLAC may take up to 6 months to start improving.

To help clear up your infection completely and to help make sure it does not return, good health habits are also required. The following measures will help reduce chafing and irritation and will also help keep the area cool and dry.

• For patients using ciclopirox for ringworm of the groin (tinea cruris):
  • Avoid wearing underwear that is tight-fitting or made from synthetic materials (for example, rayon or nylon). Instead, wear loose-fitting, cotton underwear.
  • Use a bland, absorbent powder (for example, talcum powder) or an antifungal powder (for example, tolnaftate) on the skin. It is best to use the powder between applications of ciclopirox.
• For patients using ciclopirox for ringworm of the foot (tinea pedis):
  • Carefully dry the feet, especially between the toes, after bathing.
  • Avoid wearing socks made from wool or synthetic materials (for example, rayon or nylon). Instead, wear clean, cotton socks and change them daily or more often if the feet sweat freely.
  • Wear sandals or well-ventilated shoes (for example, shoes with holes on top or on the side).
  • Use a bland, absorbent powder (for example, talcum powder) or an antifungal powder (for example, tolnaftate) between the toes, on the feet, and in socks and shoes freely once or twice a day. It is best to use the powder between applications of ciclopirox.

If you have any questions about these measures, check with your health care professional.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

• Less common--with ciclopirox shampoo
  • Fainting;  fast, pounding, or irregular heartbeat or pulse;  palpitations 
  
  

• Rare
  • Burning, itching, redness, swelling, or other signs of irritation not present before use of PENLAC 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, heck with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

• Less common--with ciclopirox shampoo
  • Dandruff;  headache;  itching skin or scalp;  oily skin;  rash;  skin disorder 
  
  

Other side effects not listed above may also occur in some patients. If you notice any other effects, check with your doctor.