Hi Frederick! Our refund and return policy is posted on our website and emails, and states our 6-month guarantee just as Ken has provided here. If you’re unsatisfied for any reason you have up to 6 months to request a refund on your most recent prescription order. We do not accept returns on nonprescription products such as shampoo, conditioner, or supplements. For more information, you can review our return policy on our FAQ page. We always encourage you to reach out with any questions, and if there's any way we can make things right we'd love to get in touch. We're rooting for you!