Drugs that can enlarge the penis are mainly hormonal drugs, but they are generally suitable for male children during the growth period. Adult males are unable to achieve permanent penis enlargement through medication, and can only achieve short-term improvement in erectile dysfunction. When puberty or growth process of male children due to androgen secretion is too small or lack of penis or penis growth slow phenomenon, can be under the guidance of the doctor through the use of gonadotropins or testosterone undecanoate and other hormones such as drugs to effectively promote the development of the penis, can effectively improve the diameter of the penis, so as to achieve the effect of penis thickening. For hereditary small penis diameter, children are unable to promote the development through hormonal drugs. The diameter and length of the penis is basically fixed at the end of the growth period. Therefore, adult males cannot take or use topical medications to thicken the penis. However, if a man experiences erectile dysfunction during sexual intercourse, it can be improved by taking tadalafil tablets or sildenafil citrate tablets. All the medications involved above should be used under medical supervision.