Yes, you may apply Markal Calamine Lotion (Bentonite, Calamine, and Glycerin) to the affected area to help soothe irritation and provide a cooling effect. Calamine can reduce itching and discomfort, while glycerin helps keep the skin moisturised. Apply it gently without rubbing or breaking the blisters, as this may cause a secondary skin infection. However, the lotion will not treat the shingles virus itself, so continue any antiviral medication prescribed by your doctor. Seek medical advice promptly if the pain, redness, or spreading of the rash worsens.