Hi, Based on the available information, it is not possible to determine the long-term safety of taking the Red Dawn Vector Shot intermittently for five years. Some of the ingredients in the shot, such as synephrine hydrochloride and 5-hydroxytryptophan, have been associated with adverse effects when taken in high doses or for prolonged periods. For example, high doses of 5-hydroxytryptophan can cause serotonin syndrome, which is a potentially life-threatening condition. Additionally, some dietary supplements, including those containing synephrine, have been associated with adverse events requiring emergency intervention. It is important to discuss any concerns or questions about supplement use with your healthcare provider, who can provide guidance on the potential risks and benefits of these products and help you make an informed decision about your care. They can also monitor your health over time and help to identify any potential adverse effects associated with long-term supplement use. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Priyanka, General & Family Physician