The body uses vitamin B12 for many important functions, including maintaining metabolism, producing DNA and red blood cells, and keeping up the health of the nervous system (1). Most people get enough of this nutrient through the food that they eat, but that’s not the case for everyone. Some people may not get enough from food, or some might require more vitamin B12 than their diet can provide. 

People who may not be getting enough vitamin B12, also known as those who have a vitamin B12 deficiency, include older adults, people who are pregnant/breastfeeding, those who follow a vegan/vegetarian diet, those who have digestive issues, and those taking certain medications. If you fall into one of these categories, the best vitamin B12 liquid drops can help to supplement your diet. 

Vitamin B12 Side Effects 

Vitamin B12 supplements are considered to be generally safe. The body will absorb as much as it needs and pass what it doesn’t through your urine. But in the case of severe vitamin B12 deficiencies where the person has to take a very high dosage, certain vitamin B12 side effects can occur. These side effects include headache, nausea and vomiting, diarrhea, fatigue/weakness, and a tingling sensation in the hands and feet (2). 

In very rare cases, vitamin B12 can cause severe allergic reactions, or anaphylaxis, that may cause the face, tongue, and throat to swell. If this occurs after you take vitamin B12, call 911 right away (3). 

There are certain medications that cause the body to absorb vitamin B12 at a lower rate. You may need to take a vitamin B12 supplement if you are on any of the following: colchicine, metformin, proton pump inhibitors, vitamin C, chloramphenicol, H2 blockers, aminosalicylic acid. Folic acid could also interfere with vitamin B12, so talk to your doctor if you are on a folic acid supplement and need to start a vitamin B12 regime. 

It may be smart to take vitamin B12 separately from the above medications so you can get the full dose of vitamin B12. For example, it may benefit you to take your medication in the morning and vitamin B12 at night, or vice versa. 

Vitamin B12 is safe to take if you are pregnant or breastfeeding, but you should not take a vitamin B12 supplement if you are allergic to vitamin B12, cobalt, or any other ingredients included in the supplement. 

If you notice any adverse effects after taking vitamin B12, stop taking it immediately. If your symptoms get worse, are severe, or don’t stop after you discontinue use, contact your doctor. 

If you experience any negative side effects while taking vitamin B12, you should try your best to get this nutrient through food instead. Some foods that offer vitamin B12 include eggs, cheese, fish, shellfish, liver, kidney, and red meat. 

Symptoms of Vitamin B12 Deficiency

The body needs an adequate amount of vitamin B12 in order to function properly, and if you are not receiving enough of this nutrient and have a deficiency, it could cause a number of symptoms to appear - and these symptoms range from mild to severe (1). 

These symptoms include skin discolorations, irregular heartbeat, abnormal gait, swelling of the tongue, numbness in the hands and feet, acute psychosis, dementia-like symptoms, irritability, and infertility. In some cases, you may have a vitamin B12 deficiency and not notice any symptoms for years. 

Use of Vitamin B12 Supplements

If you have a vitamin B12 deficiency or a condition that doesn’t allow your body to absorb vitamin B12, taking a vitamin B12 supplement can help. Here are some ways in which vitamin B12 supplements are used: 

• To treat anemia. Since vitamin B12 is essential for your body to create red blood cells, having an adequate amount in your system is crucial to avoiding anemia. Severe cases of anemia can lead to damage to the heart and nervous systems, and milder conditions can make you feel weak or fatigued. 
• Supplements can also be used to boost energy levels in those who are deficient in vitamin B12. Since this nutrient helps your body convert the food you eat into energy, the right amount in your system gives your body more fuel to work with. 
• If you have a vitamin B12 deficiency, taking a supplement may prevent birth defects, as vitamin B12 deficiencies can be dangerous to those who are pregnant or breastfeeding. A lack of vitamin B12 during this time can cause cognitive and developmental delays, neural tube defects, or failure to thrive in infants. Getting the correct dosage of vitamin B12 while pregnant or breastfeeding can ensure that your growing baby gets the nutrients they need.

Resources

1. Snyder, Cecilia. "Liquid Vitamin B12: Dosage, Benefits, and More." Healthline, 3 Jan. 2022, www.healthline.com/nutrition/vitamin-b12-liquid#types.
2. "Vitamin B-12." WebMD, 17 July 2021, www.mayoclinic.org/drugs-supplements-vitamin-b12/art-20363663.
3. Cronkleton, Emily. "Can Vitamin B-12 Cause Side Effects?" Healthline, 9 Aug. 2019, www.healthline.com/health/food-nutrition/vitamin-b12-side-effects.