Vitamin B12 has a low risk of causing harm, even at high doses. Because of this, there's currently no maximum dose that's widely recommended. However, some forms of vitamin B12 (mainly injectable and nasal B12) can cause headache or fatigue at normal doses.
When taken at appropriate doses, vitamin B-12 supplements are generally considered safe. While the recommended daily amount of vitamin B-12 for adults is 2.4 micrograms, higher doses have been found to be safe. Your body absorbs only as much as it needs, and any excess passes through your urine.
If you have any of the following health problems, consult your doctor or pharmacist before using this medication: a certain eye disease (Leber's optic neuropathy), a certain blood disorder (polycythemia vera), gout, iron or folic acid deficiency anemia, low potassium blood levels (hypokalemia).
Vitamin B12 supplements will only improve symptoms such as tiredness and lack of energy if they are caused by low vitamin B12 levels. It may take a few weeks before your vitamin B12 levels and symptoms (such as extreme tiredness or lack of energy) start to improve.
Vitamin B12
According to health experts at Click Pharmacy, as a general rule of thumb, take your B vitamins in the morning or with a meal. Vitamin B12, for example, should definitely be taken in the morning. This is because it is important for energy metabolism, which may interrupt your sleep if taken at night.
Nervous System Reactions
After getting a vitamin B12 injection some people may experience a disturbance to the nervous system. These symptoms may include dizziness, difficulty walking normally, nervousness, anxiety, weakness and uncoordinated movements.
Even the lowest doses in B12 supplements are many times the recommended dietary allowance. Doses up to 1,000 mcg, though unnecessary, aren't harmful.
Vitamin B12 deficiency can have distressing neuropsychiatric symptoms. It can have an etiological role in clinical presentations like depression, anxiety, psychosis, dementia, and delirium, requiring screening of at-risk populations.
Once you begin treating your vitamin B12 deficiency, it can take up to six to 12 months to fully recover. It is also common to not experience any improvement during the first few months of treatment. If you can, it's a good idea to address what's causing the deficiency.
Water soluble vitamins, like B12, can be tolerated at higher doses without adverse effects upon the body, and the National Academy of Medicine has not established an upper limit of Vitamin B12 intake.
The body needs vitamin B12 for normal function of the brain and nervous system, the formation of red blood cells, and other critical processes. Deficiencies in vitamin B12 can lead to symptoms like headaches, fatigue, and digestive problems and can even lead to nerve damage and cognitive issues.
Interactions between your drugs. No interactions were found between Vitamin B12 and Vitamin D3. However, this does not necessarily mean no interactions exist. Always consult your healthcare provider.
In deficient people, the benefits of B12 injections include improved mood and increased energy levels. If a doctor prescribes B12 injections, symptoms like fatigue, weakness, depression, and more may resolve within generally resolve in six to 12 weeks.
So does vitamin B12 give you energy? While B12 doesn't directly provide energy, it does give the body the tools it needs to convert food molecules into energy. Getting the recommended daily amount of B12 can therefore help ensure that the body is able to make the energy it needs to do everything you need it to do.
Recent reports suggest that, along with a B12-rich diet, consuming 500 micrograms of B12 in the form of a supplement may help individuals over 65 maintain healthy vitamin B12 levels [2]. Taking a vitamin B12 supplement may even help reverse a B12 deficiency and its symptoms, which can include: Fatigue.
B12 injections may contribute to low potassium levels in your body. Though rare, this reaction can cause muscle cramping, extreme fatigue, and an irregular heartbeat.
Fatigue. Megaloblastic anemia due to vitamin B-12 deficiency may lead to a person feeling fatigued. Without enough red blood cells to carry oxygen around their body, a person can feel extremely tired.
Vitamin B12 deficiency can indeed lead to weight gain. But the weight gain is not a direct result of the deficiency. Instead, vitamin B12 deficiency causes lethargy or lack of energy, and in turn, inactivity causes weight gain.
Antibiotics, Tetracycline: Vitamin B12 should not be taken at the same time as tetracycline because it interferes with the absorption and effectiveness of this medication.
If your vitamin B12 deficiency is not caused by a lack of vitamin B12 in your diet, you'll usually need to have an injection of hydroxocobalamin every 2 to 3 months for the rest of your life.
Due to its special role, vitamin B12 aids in the prevention of anemia, which mostly leads to fatigue. Even though the research available about the relationship between vitamin B12 and insomnia remains unclear, some studies² show that elevated levels of vitamin B12 do cause sleeplessness.