How does Zostrix work? There are many topical analgesic creams available to help relieve pain, derived from the humble chili, most are in the form of capsicum. Capsicum can be found in products such as heat rubs (rubefacients). Capsaicin is also derived from chili peppers, and when purified works at a pharmacological level. Purified capsaicin … Continue reading How does Zostrix work?