Given that he has thyroid and diabetes, any treatment cannot be recommended without proper analysis. Would recommend that you consult a doctor, preferably someone who is nearby where you live. It would help if your father requires an in person examination.
Disclaimer : The content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding your medical condition. Never disregard professional medical advice or delay in seeking it because of something you have read on this website.