Vitamin B12 toxicity is essentially a condition that develops when a person takes too much vitamin B12 and begins to develop side effects such as bloating or diarrhea as a result. A person would likely have to take massive doses of vitamin B12 for it to cause toxicity, as the vitamin is generally very well tolerated. To avoid developing this condition, a person can consult their doctor or a nutrition expert for safe levels of vitamin B12 supplementation. An individual is unlikely to develop toxicity from vitamin B12 ingested in the course of a normal diet.
While a person may want to keep their vitamin B12 intake to levels suggested by their doctor or nutrition expert, it is interesting to note that no levels of toxicity are reported. This means that scientists have not established levels at which this vitamin can become toxic. In fact, research studies have failed to identify precise symptoms of vitamin B12 toxicity. As such, there is no maximum daily dose recommendation.
Although vitamin B12 is unlikely to be toxic, even at higher levels, there are some symptoms that could be associated with taking too much. If unpleasant symptoms develop when a person takes vitamin B12, this may mean that they have taken too much for their body, even though the same amount may not cause problems in the average person. Among the symptoms that may develop in such a case are diarrhea and swelling throughout the body. An individual with vitamin B12 toxicity could develop blood clots in their legs as well.
It is important to note that a person could develop allergy symptoms while taking vitamin B12. However, such symptoms generally do not mean that a person is experiencing vitamin B12 toxicity. Instead, it usually means that he is actually allergic to the vitamin supplement or something that was used to make it. Possible allergy symptoms include hives or a rash anywhere on the body, swelling of the face, swelling of the mouth or throat, difficulty breathing, and wheezing. If an individual develops allergy symptoms that he believes are related to vitamin B12 supplementation, he should stop taking supplements and contact his doctor for advice.
A person who takes vitamin B12 through injections, usually in the course of some type of medical therapy, may have a slightly increased risk of developing vitamin B12 toxicity. You are also more likely to develop an allergic reaction to the vitamin. Like those who take it orally, it's important to report unusual symptoms to a healthcare professional as soon as possible.