Sometimes patients stop medications for diabetes due to fear of hypoglycemia or unscientifically reduce the dose. This can lead to high blood sugars during the day which can lead to excessive tiredness, hunger, thirst, excessive urination, electrolyte imbalance and weight loss. These patients can sometimes slip into serious consequences like diabetes ketoacidosis and hyperosmolar coma.
You should always seek medical advice during medication dose adjustment and monitor blood sugars during the fast.