2 / 8 A safer alternative is to use natural, non-toxic remedies that are easy to make at home. Ingredients like onion, gram flour, baking soda, red chili powder, and lemon juice can be combined to create a mixture that effectively repels rats. Mix in one teaspoon each of gram flour, baking soda, and red chili powder. Even if they are drawn to the sugar, they cannot eat the spicy mixture. ADVERTISEMENT7 / 8 By following these simple home remedies, you can keep your house rat-free without using harsh chemicals.