4-year-old children can drink vitamin C effervescent tablets, but long-term use is not recommended. Vitamin C effervescent tablets can enhance the body’s resistance, can be used for the prevention and treatment of a variety of acute and chronic infectious diseases or other diseases, but also can be used for the recovery period after the disease, trauma healing period and allergic diseases, such as adjuvant therapy.4-year-old children can follow the doctor’s instructions to apply the drug if the indications are met and there are no relevant contraindications. It is contraindicated in children 4 years of age who are hypersensitive to any of the active ingredients or excipients in vitamin C effervescent tablets. Vitamin C effervescent tablets should be dissolved in cold or lukewarm water and should not be taken directly by mouth. Vitamin C effervescent tablets should not be used in children 4 years of age for prolonged overdose, but should be used in accordance with medical advice.