Your doctor will provide instructions on how to properly use Casthrin 5 Lotion and the recommended dosage To ensure correct usage refer to the instructions provided with the medication Prior to application ensure that your skin is clean dry and cool Thoroughly wash your entire body 814 hours after using this medicine In most cases one application is sufficient to treat the condition However if a second application is required wait at least 7 days before applying it again It is possible for itching to persist for a few weeks after treating scabies This is likely an allergic reaction to dead mites and not an indication of treatment failure Mild burning stinging or tingling may occur at the application site which are the most common side effects These side effects are typically mild and may not affect everyone If you have any preexisting skin conditions allergies to medicines food or other substances or if you have asthma inform your doctor before using this medication Although this medicine is generally considered safe it is advisable to consult your doctor if you are pregnant or breastfeeding