10 doctors weighed in:
How unsafe is a one-day megadose of vitamin a, taken to help knock out a nascent cold? (24, 000 i.U., then 24, 000 8 hrs. Later).
10 doctors weighed in

Dr. Yo-El Ju
Neurology
4 doctors agree
In brief: Not helpful
Vitamin a has not been shown to help with the common cold (uri).
Excessive vitamin a can cause pseudotumor cerebri and consequent blindness.

In brief: Not helpful
Vitamin a has not been shown to help with the common cold (uri).
Excessive vitamin a can cause pseudotumor cerebri and consequent blindness.
Dr. Yo-El Ju
Dr. Yo-El Ju
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Dr. Shaym Puppala
Internal Medicine
3 doctors agree
In brief: Not likely to help
A one-time dose like this is unlikely to kill, but also unlikely to help.
It is an entirely unnatural amount of vitamin a to ingest, and there is some evidence that taking vitamin a supplements could be harmful to the heart and the bones, and could increase risk of cancer. This would be much more likely for daily use than from one-time use, but not worth the risk in my opinion.

In brief: Not likely to help
A one-time dose like this is unlikely to kill, but also unlikely to help.
It is an entirely unnatural amount of vitamin a to ingest, and there is some evidence that taking vitamin a supplements could be harmful to the heart and the bones, and could increase risk of cancer. This would be much more likely for daily use than from one-time use, but not worth the risk in my opinion.
Dr. Shaym Puppala
Dr. Shaym Puppala
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Dr. Richard Bensinger
Ophthalmology
1 doctor agrees
In brief: No harm
These dosages are not going to cause any harm. However, there is no data to support the use of vitamina as a supressant of a cold or upper respiratory infection.
You are supporting the supplement industry but not yourself.

In brief: No harm
These dosages are not going to cause any harm. However, there is no data to support the use of vitamina as a supressant of a cold or upper respiratory infection.
You are supporting the supplement industry but not yourself.
Dr. Richard Bensinger
Dr. Richard Bensinger
Thank
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