Vitamin D, blind supplement is not good, dare not supplement it is not right

*Only for medical professionals to read and refer to the 51st article related to the prevention and treatment of osteoporosis published by Director Bian Pingda of Zhejiang Provincial People's Hospital in the medical community
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In recent years, with the continued promotion of health promotion, the importance of vitamin D supplementation has gradually been recognized
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However, in clinical work, although it is possible to encounter patients who blindly increase the dose or prolong the course of treatment, it is more common for patients who are afraid to supplement vitamin D because of fear of vitamin D poisoning
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Cases of poisoning due to ordinary vitamin D supplementation are extremely rare.
In the past ten years, I have investigated more than 1,600 cases of vitamin D supplementation in middle-aged and elderly people, and no cases of poisoning due to ordinary vitamin D supplementation have been found [1]
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As can be seen from the following two cases, supplementation of ordinary vitamin D rarely causes poisoning
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44-year-old Ms.
Jiang bought 5,000 International Units (IU) of vitamin D3 soft capsules from the Internet at her own expense two and a half years ago.
The recommended dosage of this soft capsule is to take 1 capsule every other day, but Ms.
Jiang insisted that she should take 3 capsules per day.
～4 capsules, after 2.
5 years of continuous use, the 25-hydroxyvitamin D (total) was recently measured to be 133.
02ng/ml (Figure 1), but Ms.
Jiang currently has no discomfort such as anorexia, fatigue, and serum calcium and creatinine are also normal.

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Figure 1 Ms.
Jiang's vitamin D test results (mass spectrometry) 63-year-old Ms.
Shen started intramuscular injection of vitamin D2 (200,000 IU, once every 2 weeks) in the community two years ago
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Although her monthly injection dose (400,000 IU) was less than the recommended dose (600,000 IU, IM once a month), the duration was long
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The recent outpatient vitamin D test result was 103.
3 ng/ml (Figure 2).
Ms.
Shen has no discomfort such as anorexia and fatigue, and her serum calcium and creatinine are normal
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Figure 2 The results of the vitamin D test of Ms.
Shen (mass spectrometry) Although the above two ladies continue to supplement vitamin D, with the further increase of the 25-hydroxyvitamin D level (eg > 200ng/ml) [2], there may be Poisoning symptoms, but in real life, there are very few people who take long-term and excessive vitamin D supplementation like the two of them.
Therefore, it is very safe to supplement vitamin D reasonably, and there is no need to worry too much about the manifestations of poisoning
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Selecting large doses is helpful for rapid vitamin D supplementation.
The "Guide" recommends that the daily intake of vitamin D for middle-aged and elderly people should be 400-600 IU, and the maximum tolerated intake is 2000 IU per day [3]
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However, the international dose of vitamin D supplementation is much larger.
For example, the North American Endocrine Society recommends that adults with vitamin D deficiency should be given 50,000 IU of vitamin D3 or D2 per week (generally need to be taken continuously for more than 8 weeks).
After 30ng/ml, use 1500-2000IU per day to maintain [2]
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Due to the lack of the above-mentioned high-dose oral vitamin D preparations in the domestic medical market, in recent years, we have chosen to inject the national essential drug vitamin D2 injection, 600,000 IU intramuscularly every month, and found that a 25-hydroxyvitamin D was less than 15ng/ It takes an average of 6 months for patients with ml to make up to normal (≥30ng/ml, mass spectrometry) [4]
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When supplementing vitamin D, although the selected dose is smaller and safer, the longer it takes to supplement to normal, and the fewer patients who can adhere to supplementation.
Therefore, it is recommended to choose a large dose for vitamin D supplementation.
Of course, regular testing should be paid attention to.

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Excessive intake of active vitamin D is a common cause of vitamin D poisoning.
As we all know, ordinary vitamin D (including vitamin D3 soft capsules and vitamin D2 injection) enters the body and needs to be converted into 1,25-bis through hydroxylation in the liver and kidneys, respectively.
Hydroxyvitamin D only works
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The elderly are prone to 1,25-dihydroxyvitamin D deficiency due to the lack of vitamin D in the body and the decline of liver and kidney function.
Therefore, it is recommended that the elderly take active vitamin D.

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Calcitriol capsules (ie, 1,25-dihydroxyvitamin D) can be directly absorbed after taking it to promote the absorption of calcium
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However, the safety window of calcitriol is narrow (that is, the therapeutic dose is close to the toxic dose).
Even if the prescribed dose (0.
50 μg per day, or 2 capsules) is taken, some people will experience symptoms of vitamin D poisoning, manifested as decreased appetite.
, fatigue, increased serum calcium and creatinine
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Therefore, it is generally recommended that calcitriol capsules should be started with a small dose (1 capsule per day) [1]
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Calcitriol capsules take effect quickly and fail quickly after taking them.
Therefore, for patients who are poisoned due to overdose of calcitriol capsules, they only need to stop taking the medicine.
relief within days
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References: [1] Zhang Chenyang, Bian Pingda, Shou Zhangxuan, et al.
Status and countermeasures of vitamin D deficiency in the elderly [J].
China Journal of New Drugs and Clinical Medicine, 2019, 38(6): 328-332.
, [ 2] Liao Xiangpeng, Zhang Zengli, Zhang Honghong, et al.
Application Guidelines for Vitamin D and Bone Health in Adults (2014 Standard Edition) [J].
Chinese Journal of Osteoporosis, 2014, 20(9): 1011-1025.
[3] Zhonghua Osteoporosis and Bone Mineral Disease Branch of the Medical Association.
Guidelines for the diagnosis and treatment of primary osteoporosis (2017) [J].
Chinese Journal of Osteoporosis and Bone Mineral Disease, 2017, 10(5): 413-436 .
[4]Bian PD, Jin X, Shou Zh X, Effects of Monthly Intramuscular high-Dose vitamin D2 on serum 25-hydroxyvitamin D and immune parameters in very elderly Chinese patients with vitamin D deficiency[J].
Int J Endocrinology, 2021 , 1343913.