1. People with poor kidney function should not take more vitamin C. Long-term overdose of vitamin C may cause hyperacidity, gastric reflux, and even urinary system stones. Especially people with kidney deficiency should take less vitamin C.

2. Do not stop taking vitamin C suddenly after taking a large amount of vitamin C. If you stop taking vitamin C suddenly, it will cause a drug withdrawal reaction and worsen or relapse symptoms. You should gradually reduce the dosage until the drug is completely stopped.

3. Vitamin C should not be used in combination with isoniazid, aminophylline, streptomycin, penicillin and sulfa drugs; otherwise, the efficacy of the above drugs will be reduced or ineffective due to the acidic environment.

Extended information

The official recommended intake of vitamin C:

1. The British Food Standards Agency proposes: 40 mg per day.

2. The World Health Organization proposes: 45 mg per day.

3. The National Science Association of the United States proposes: 60-95 mg per day.

4. The United States officially defines the Tolerable Upper Intake Level (Tolerable Upper Intake Level) for a 25-year-old male as 2,000 mg per day.

Baidu Encyclopedia - Vitamin C

Baidu Encyclopedia - Vitamin C