What Is a Vitamin Overdose?

Vitamin poisoning is a toxic condition that occurs after taking too much vitamins. For years, children and athletes have been thought to need a lot of vitamins. In recent years, some people have suggested that the use of high-dose vitamins can prevent cancer, can treat hyperlipidemia and arteriosclerosis, etc., so-called "high-dose vitamin therapy" has appeared, increasing the chance of people taking excessive vitamins.

Basic Information

English name

vitamin D intoxication

Visiting department

Emergency Department

Common causes

Taking excess vitamins

Common symptoms

Loss of appetite, irritability or lethargy, vomiting, swelling of the front palate, enlarged head circumference, suspicious craniotomy, and papilledema

Clinical manifestations of vitamin poisoning

Vitamin A

(1) Acute type Due to individual differences in the sensitivity of children to vitamin A, and the amount of vitamin A stored in the liver, the poisoning dose may vary greatly. In general, vitamin A injection of 300,000 IU can cause symptoms of poisoning within a few days. Presented as loss of appetite, irritability or lethargy, vomiting, bulging of the anterior palate, enlarged head circumference, suspicious craniotomy, and papilledema. Elevated intracranial pressure is common in the acute type, which may be caused by increased cerebrospinal fluid or malabsorption.

(2) Chronic vitamin A dosage amounts to tens of thousands of units per day. For example, if infants and young children consume daily vitamin A of 1500 IU per kilogram of body weight, symptoms of poisoning may occur after several days. Early onset of irritability, loss of appetite, low fever, sweating, hair loss, and later typical bone pain symptoms, metastatic pain, may be accompanied by swelling of soft tissues, tender points without redness and heat signs, more common in long bones and limb bone Because long bones are embedded in the epiphysis, they can be short. Some cases have swelling and pain in the temporal and posterior occipital regions, which can be misdiagnosed as skull softening. Symptoms of increased intracranial pressure, such as headache, vomiting, wide and raised anterior condyle, separation of skull sutures, esotropia in both eyes, nystagmus, and diplopia are another characteristic of this disease, but they are rarer than the acute type. In addition, itching, desquamation, rash, cleft lip and palate, dry hair, liver and splenomegaly, abdominal pain, myalgia, bleeding, kidney disease, and hypoplastic anemia with reduced white blood cell count. Increased blood alkaline phosphatase.

2. Vitamin D

Vitamin D is the most susceptible to poisoning among all vitamins. The main symptoms and signs of poisoning are: hypercalcemia, muscle weakness, indifferent feelings, headache, anorexia, nausea, vomiting, bone pain, ectopic calcification , Proteinuria, hypertension and arrhythmia. Chronic hypercalcemia can lead to systemic vascular calcification. Renal calcium deposits and rapid decline in renal function. Symptoms of poisoning can occur when taking 60,001 U (1.25 mg) daily.

3. Vitamin E

Taking large doses of vitamin E for a long time is not easy to cause poisoning, but if you take 300-800 mg per day, you will have symptoms of muscle weakness, fatigue, headache and nausea. Vitamin E excess can also cause major bleeding. For people taking blood clotting-lowering drugs such as aspirin, vitamin E overdose is more dangerous.

4. Vitamin K

Excessive vitamin K can cause cancer and rashes in the body. Pregnant women taking high doses of vitamin K can cause neonatal jaundice. Taking multivitamins high in vitamin K also affects the effectiveness of oral anticoagulants.

5. Vitamin B

Most people take 20 mg of vitamin B ₆ daily without side effects. Taking 25 mg per day has an antagonistic effect on levodopa (a drug for treating Parkinson's disease), reduces the effect of levodopa, a small dose of vitamin B ₆ , and also reduces the anticonvulsant effects of barbiturate and phenytoin. Sometimes in order to treat premenstrual syndrome, long-term high doses (several grams per day) of vitamin B _{6 are} needed, which can cause severe peripheral neuritis.

Vitamin B ₃ helps to expand blood vessels and increase blood flow. It is also related to energy conversion. The recommended adult intake is 20 mg per day. People with a normal diet do not need to take extra vitamin B ₃ .

A slight excess of vitamin B ₃ can cause redness, headache, itching, and stomach problems in the face and shoulders. A severe overdose can cause oral ulcers, diabetes and liver damage.

Vitamin B _{5 is} mainly involved in the body's metabolic activities. The recommended adult intake is 4 to 7 mg per day. People with a normal diet do not need to consume additional B ₅ .

6. Vitamin C

Some people advocate long-term use of large doses of vitamin C to prevent colds and cancer, and lower blood lipids, but excessive poisoning should be strictly prevented. There are currently reports that diarrhea can occur with 1 g daily. Taking 4 grams at a time results in uric aciduria. Long-term high-dose administration causes some patients to form urinary oxalate stones and hemolysis in patients with glucose 6-phosphate dehydrogenase (G-6-PD) deficiency. Pregnant women taking large doses of vitamin C can cause infants with scurvy.