Vitamin AD drops are vitamin A, D two vitamin complex preparation, according to its applicable age is divided into two specifications for less than 1 year old and more than 1 year old. Nine-month-old babies can take vitamin AD drops over 1 year old, but it is not recommended to take, need professional physician to adjust the use of the dose, it is recommended that it is best to eat the dose specifications suitable for babies less than 1 year old. Vitamin AD drops are mainly used for the treatment and prevention of vitamin A and D deficiencies, such as night blindness, rickets, hand and foot tics. The drug is available in two dosage sizes: under 1 year old and over 1 year old. The over 1 year old dosage size contains more vitamin A and vitamin D than the under 1 year old dosage size. Overdose of vitamin AD drops, chronic toxicity may occur, such as bone and joint pain, itchy skin, dry and cracked lips, fever, headache, vomiting, diarrhea and other symptoms. Therefore, 9-month-old babies can take vitamin AD drops above 1 year of age, but it is recommended to adjust the dose of medication under the guidance of a doctor; it is best to use directly the vitamin AD drops suitable for babies under 1 year of age.