Compounded medications are not reviewed or verified by the FDA for safety, effectiveness, or quality and are not FDA-approved. Instead, compounded drugs may be prepared, or compounded, for patients who cannot be treated with an FDA-approved medication. In situations like this, compounding can serve important patient needs. A licensed healthcare provider will evaluate if treatment involving a compounded medication is necessary or appropriate for you. 503A pharmacies are required to comply with FDA rules, regulations, and guidance, among other applicable laws, rules, regulations, and guidance.