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SCIENTIFIC SCORE
Possibly Effective
Based on 1 Research
7
USERS' SCORE
Good
Based on 4 Reviews
8.2
Supplement Facts
Serving Size: 1 Tablet
Amount Per Serving
%DV
Vitamin B12(as Methylcobalamin)
5,000 mcg
208,330%
Top Medical Research Studies
7
Vitamin B12 hypersensitivity studied
Vitamin B Hypersensitivity: A Retrospective Multicenter Study.
Relevant findings on allergies
We explored a group of 29 patients who were referred to three allergy centers in the UK due to suspected vitamin B12 hypersensitivity (VB12H). Over the period from 2014 to 2022, these patients underwent various tests, including skin prick tests and drug provocation tests. The aim was to understand how vitamin B12 treatment relates to allergies and to develop a reliable method for assessing hypersensitivity.
Among the patients, 62% displayed immediate hypersensitivity reactions, with some experiencing severe anaphylaxis to vitamin B12 forms. Interestingly, we found that some patients who were sensitized to a specific type of vitamin B12 could tolerate another form. This indicates that not all vitamin B12 treatments may cause problems for everyone. However, confirmed cases of VB12H are considered to be quite rare.
Overall, while we identified individual cases where vitamin B12 treatment provoked allergic responses, the evidence suggests that vitamin B12 hypersensitivity is uncommon. This nuances the discussions around vitamin B12 treatment face since adverse reactions are not widespread. Our proposed evaluation protocol includes skin testing and considerations for allergies to related substances, such as polyethylene glycol.
Therefore, while there is an observable connection between vitamin B12 and allergic reactions in a small subset of individuals, the study indicates that treatment for vitamin B12 deficiency remains generally safe for most individuals.
Among the patients, 62% displayed immediate hypersensitivity reactions, with some experiencing severe anaphylaxis to vitamin B12 forms. Interestingly, we found that some patients who were sensitized to a specific type of vitamin B12 could tolerate another form. This indicates that not all vitamin B12 treatments may cause problems for everyone. However, confirmed cases of VB12H are considered to be quite rare.
Overall, while we identified individual cases where vitamin B12 treatment provoked allergic responses, the evidence suggests that vitamin B12 hypersensitivity is uncommon. This nuances the discussions around vitamin B12 treatment face since adverse reactions are not widespread. Our proposed evaluation protocol includes skin testing and considerations for allergies to related substances, such as polyethylene glycol.
Therefore, while there is an observable connection between vitamin B12 and allergic reactions in a small subset of individuals, the study indicates that treatment for vitamin B12 deficiency remains generally safe for most individuals.
Read More
Most Useful Reviews
9.5
Effective ingredient choices
This is an excellent quality product. The carefully selected ingredients did not cause any allergies or negative reactions. The large package size lasts long, with average-sized capsules that have a neutral taste. I noticed improvements within a week; my intestinal function and metabolism have enhanced while my nervous system feels more stable. I have no doubts about its effectiveness in treating allergies.
Read More
9
Positive allergen response
The best tasting B-12 I've tried; previous options were only average. I enjoy taking these lozenges as they have a great flavour and no bitter aftertaste. The ingredients are suitable for my allergies to dairy and soy. Even though I used to favour injections, I will supplement with these. I appreciate the variety, pricing, and service from iHerb.
Read More
0.5
Allergy symptoms experienced
I believe this product caused nose itching and a runny nose, so I stopped using it.
Read More
Medical Researches
SCIENTIFIC SCORE
Possibly Effective
Based on 1 Research
7
7
Vitamin B12 hypersensitivity studied
Vitamin B Hypersensitivity: A Retrospective Multicenter Study.
Relevant findings on allergies
We explored a group of 29 patients who were referred to three allergy centers in the UK due to suspected vitamin B12 hypersensitivity (VB12H). Over the period from 2014 to 2022, these patients underwent various tests, including skin prick tests and drug provocation tests. The aim was to understand how vitamin B12 treatment relates to allergies and to develop a reliable method for assessing hypersensitivity.
Among the patients, 62% displayed immediate hypersensitivity reactions, with some experiencing severe anaphylaxis to vitamin B12 forms. Interestingly, we found that some patients who were sensitized to a specific type of vitamin B12 could tolerate another form. This indicates that not all vitamin B12 treatments may cause problems for everyone. However, confirmed cases of VB12H are considered to be quite rare.
Overall, while we identified individual cases where vitamin B12 treatment provoked allergic responses, the evidence suggests that vitamin B12 hypersensitivity is uncommon. This nuances the discussions around vitamin B12 treatment face since adverse reactions are not widespread. Our proposed evaluation protocol includes skin testing and considerations for allergies to related substances, such as polyethylene glycol.
Therefore, while there is an observable connection between vitamin B12 and allergic reactions in a small subset of individuals, the study indicates that treatment for vitamin B12 deficiency remains generally safe for most individuals.
Among the patients, 62% displayed immediate hypersensitivity reactions, with some experiencing severe anaphylaxis to vitamin B12 forms. Interestingly, we found that some patients who were sensitized to a specific type of vitamin B12 could tolerate another form. This indicates that not all vitamin B12 treatments may cause problems for everyone. However, confirmed cases of VB12H are considered to be quite rare.
Overall, while we identified individual cases where vitamin B12 treatment provoked allergic responses, the evidence suggests that vitamin B12 hypersensitivity is uncommon. This nuances the discussions around vitamin B12 treatment face since adverse reactions are not widespread. Our proposed evaluation protocol includes skin testing and considerations for allergies to related substances, such as polyethylene glycol.
Therefore, while there is an observable connection between vitamin B12 and allergic reactions in a small subset of individuals, the study indicates that treatment for vitamin B12 deficiency remains generally safe for most individuals.
Read More
User Reviews
USERS' SCORE
Good
Based on 4 Reviews
8.2
9.5
Effective ingredient choices
This is an excellent quality product. The carefully selected ingredients did not cause any allergies or negative reactions. The large package size lasts long, with average-sized capsules that have a neutral taste. I noticed improvements within a week; my intestinal function and metabolism have enhanced while my nervous system feels more stable. I have no doubts about its effectiveness in treating allergies.
Read More
9
Positive allergen response
The best tasting B-12 I've tried; previous options were only average. I enjoy taking these lozenges as they have a great flavour and no bitter aftertaste. The ingredients are suitable for my allergies to dairy and soy. Even though I used to favour injections, I will supplement with these. I appreciate the variety, pricing, and service from iHerb.
Read More
8.8
Pain relief
Fast help for B12 deficiency. I was experiencing severe pain in my hands due to carpal tunnel syndrome, and the tingling in my lips and face was attributed to allergies. After researching, I discovered I had symptoms of B12 deficiency. Taking JARROW Methyl B-12 for five weeks has alleviated the tingling and reduced the pain significantly, aiding in my recovery. I plan to continue using it as it’s made a remarkable difference.
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0.5
Allergy symptoms experienced
I believe this product caused nose itching and a runny nose, so I stopped using it.
