B12 Shot Side Effects – Do They Outweigh the Risk?
Medically reviewed by Leann Poston, M.D. on 9/29/20
As vitamin B12 continues to gain popularity and attention, many are beginning to wonder what the B12 shot side effects and benefits are? Can this supplement really be as great as everyone keeps saying it is with no risks or side effects? While this treatment still fascinates us today and poses many questions, the history of the development of B12 shots is just as interesting.
In the 1850s, pernicious anemia was essentially a fatal condition – in today’s medicine, pernicious anemia is easily treated with B12 supplements. However, in the 1850s, patients suffered from abnormal gait, exhaustion, and inevitably they ended up in the hospital before they passed. It wasn’t until the 1920s when Georges Richard Minot and William Parry Murphy determined that certain foods (red meat and liver) effectively treated anemia in dogs. Almost 50 years later, Robert Woodward, an organic chemist, successfully synthesized vitamin B12. From this discovery, modern medicine created treatments based on the discovery of vitamin B12’s role in anemia and the successful synthesis of its complex structure.
Thankfully, conditions caused by vitamin B12 deficiencies are incredibly treatable through vitamin B12 supplements. Understanding the B12 shot side effects and benefits can help you manage your expectations of vitamin B12 as a treatment and whether a B12 shot it the best form of treatment.
Vitamin B12 – What It is and What It Does
Vitamin B12, also known as cyanocobalamin, is an important factor in DNA synthesis, the metabolism of every cell within the body, the maturation of developing red blood cells, and the metabolism of fatty acids and amino acids. Because vitamin B12 is such an integral component in the function of a healthy body, maintaining the proper levels of B12 within the body is absolutely necessary to sustain a properly working nervous system and a healthy red blood cell count.
Vitamin B12 is most commonly sourced through foods that come from animals such as fish, red meat, eggs, dairy, cheese, and other dairy products. Those who are vegan or vegetarian sometimes source their B12 through fortified cereals. While many people can consume and absorb the proper amount of vitamin B12 through their dietary choices, many people cannot sustain the proper levels of B12 within their body, which can lead to dangerous conditions if left untreated.
Vitamin B12 deficiencies are rare in otherwise healthy individuals; however, those at an elevated risk at groups who do not consume a diet with animal-sourced food, as well as those suffering from other health conditions. Groups at an increased risk of developing a vitamin B12 deficiency are:
- Adults over 50
- Those with low gastric intrinsic factor
- Those with a low amount of stomach acid
- Those taking certain medications
- Gastrointestinal disorders like Crohn’s disease and celiac disease
- Those who have had weight loss surgery, bowel resection, or surgery on another part of the digestive tract
- Those who take metformin and acid-reducing medications
- Those with specific genetic mutations, such as MTHFR, MTRR, and CBS
- Those who regularly consume alcoholic beverages (NIH, n.d.)
If someone fits into one of these at-risk groups, it is best to consult your doctor in considering whether or not you should undergo testing to determine if you have a vitamin B12 deficiency. Presently, no one test determines whether or not someone is deficient in vitamin B12. Doctors must consider both lab results and clinical conditions to reach a diagnosis.
Symptoms of B12 Deficiency
Before considering both the B12 shot side effects and the B12 shot benefits, it is important to understand the symptoms of a vitamin B12 deficiency. Individuals cannot procure vitamin B12 without a prescription, and in order to obtain a prescription, you must be deemed deficient. It can be especially tricky to reach this diagnosis as there is no “gold-standard” test, and symptoms can long go unnoticed or be contributed to other causes.
Consider that vitamin B12 is responsible for so many bodily functions; the displayed symptoms and affected body systems can vary greatly. Another problem is that symptoms and their onset tend to increase gradually, again making it hard to connect the dots between symptoms and cause. Listed below are just a few of the symptoms caused by a vitamin B12 deficiency:
- Abnormal reflexes
- Tingling, numbness, or other neuropathies
- Impaired sense of position
- Weakness in arms or legs
- Dizziness, vertigo, or balance issues
- Difficulty walking or abnormal gait
- Confusion or memory loss
- Restless legs
- Vision problems
- Anger and irritability
- Personality changes
- Mania and/or psychosis
- Violent and antisocial behavior
- General weakness
- Shortness of breath or difficulty breathing
- White appearance; pallor
- Fatigue or general tiredness
- Coordination and balance problems while walking
- Difficulty focusing
- Memory loss
- Sleep issues
- Hair loss
- Loss of appetite
- Swollen tongue.
- Fast heart rate
- Shortness of breath
- Mouth pain
- Weight loss
Keeping an eye out and paying close attention to these symptoms can help in accurately diagnosing a vitamin B12 deficiency. If you think you may be deficient in vitamin B12, it is important to contact a health care professional and schedule a consultation.
Also read – How to Buy BPC-157 Online Safely
Treatment for Vitamin B12 Deficiency
Fortunately, there are many options in modern medicine to safely and successfully treat vitamin B12 deficiency. There are three main treatment methods – a change in diet, oral supplements, and vitamin B12 injections. For those who aren’t receiving enough vitamin B12 as a result of food choices may be able to treat their deficiency by incorporating more vitamin B12 rich foods in their diets.
However, for those deficient as a result of age, a genetic mutation, stomach issues, or those taking certain medications, a change in diet may not be enough to treat a vitamin B12 deficiency. These individuals will likely have to supplement their diet with an oral B12 supplement or a B12 injection. Oral supplements are considered inferior to the vitamin B12 injections as they take longer to absorb, and some of the nutritional value is lost during digestion in the stomach.
For those receiving B12 shots as a treatment to a B12 deficiency, there are a few different forms, or vitamers, of synthesized vitamin B12 that can be used to handle the deficiency. These include:
- Cyanocobalamin – This vitamer is used for food fortification, multi-vitamin products, and dietary supplements. Cyanocobalamin is suitable for these methods of treatment because of its stability during processing and storage.
- Hydroxocobalamin – This vitamer is typically found within the pharmacology. Due to its water solubility, it is commonly used for intramuscular or intravenous injections. Also used to reverse the effects of cyanide poisoning, this vitamer is the preferred course of treatment for those with intrinsic cobalamin metabolic disease and those with optic neuropathy as a symptom of pernicious anemia.
- Adenosylcobalamin – This vitamer is an active cofactor form of vitamin B12. It naturally occurs in the liver and is active in the mitochondria.
- Methylcobalamin – This vitamer is an active form of B12 that works with several enzymes to create amino acids, produce red blood cells, repair DNA, and assist with other essential physiological processes. This form of B12 is typically administered through injections and oral supplements.
Determining the right course of treatment for a vitamin B12 deficiency is between the patient and their healthcare provider. Above all, the most important thing is that the deficiency is properly treated, treatment is working well, and the quality of the patient’s life is improving.
Vitamin B12 Shot Benefits
There are both vitamin B12 shot side effects and vitamin B12 shot benefits. Many of the benefits associated with the vitamin B12 shot include better mood, increased energy, alleviating anemia symptoms, weight loss, and many more. Though keep in mind, that these benefits are realized when a vitamin B12 deficiency is reversed. As with any treatment, it is incredibly important to weigh both the risks and benefits associated with the course of treatment. To give you a better idea, listed below are the benefits associated with vitamin B12 shots:
- Helping with red blood cell formation which may boost energy and endurance
- May support heart health by decreasing homocysteine levels
- May help prevent cognitive decline
- Anemia prevention (NIH, n.d.)
- May reduce the risk age-related macular degeneration
- May improve sperm count (Penn State, 2011)
While these are only some of the benefits associate with vitamin B12 shots, it is easy to see that vitamin B12 is responsible for so many functions within the body. Considering a deficiency can cause harm to many systems within the body, understanding the benefits of the B12 shot and know how it could improve the quality of your life is very important to leading a safe and healthy life.
Also read – What is the Right BPC-157 Dosage?
B12 Shot Side Effects
Just as it is important to understand the benefits of the B12 shot, it is also incredibly important to know the B12 shot side effects. Before anyone makes a decision regarding their health, it is imperative that they know the risks and the benefits. Understanding both the B12 shot side effects, as well as the B12 shot side effects at the injection site, is important because it empowers you to make a decision regarding your treatment that is fully informed.
B12 shot side effects include, but are not limited to:
- Swelling at the injection site
- Mild diarrhea
- Swelling in the body
- Low potassium
- Skin rash
- Pulmonary edema and congestive heart failure (in early treatment)
- Vein thrombosis
- Polycythemia vera
- A very rare, but serious allergic reaction causing swelling of the face, tongue, and throat, and difficulty swallowing or breathing (anaphylaxis)
- High blood pressure immediately after injection
- Cold symptoms
- Burning skin
- Pink or red skin discoloration
- Joint and muscle pain
- Facial swelling
- Increase and blood volume and red blood cells
Considering the B12 shot side effects listed above, it is important to understand that some of these side effects are more common, while others are incredibly rare. This is another important discussion topic to bring up with your health care provider when evaluating your diagnosis and considering treatment.
Frequently Asked Questions
Below are some common concerns and questions people have when considering a vitamin deficiency and the B12 shot side effects and benefits associated with this specific treatment. Read below to see if a question you may have is present or use these topics as a way to start a conversation with your health care provider.
Are Vitamin B12 Shots More Effective Than Vitamin B12 Oral Supplements?
Both methods of treatment can deliver the desired results, and the majority of the “success” of treatment is determined on a case-by-case basis and what is most comfortable and effective for the individual patient. Some studies have shown that a high-dose, oral vitamin B12 was as effective as an intramuscular injection; however, other studies have determined that oral B12 supplements aren’t as fully absorbed during the digestive process. It’s best to talk with your doctor to determine which form of treatment is best for you.
Are Vitamin B12 Shots painful?
While this is somewhat dependent on the individual’s tolerance for pain, B12 injections are mostly considered to be relatively painless. Injections given into the muscle typically present some pain, swelling, and itching at the injection site. However, these symptoms are mild and wear off pretty quickly.
Any time we are faced with unfamiliar medical treatments, it is understandable to have questions and concerns. It makes sense to wonder if the benefits outweigh the B12 shot side effects. Considering how important vitamin B12 is to the optimal function of your body; it seems as though the answer would be, yes.
When you’re ready to talk to your doctor about your prescription for your vitamin B12 deficiency, you will want to ensure that you are sourcing your vitamin B12 supplement from the best place possible.
A great place to source your vitamin B12 supplement is through Invigor Medical. This trusted, U.S. Pharmacy provides high-quality methylcobalamin to those deficient in vitamin B12 with a prescription for an injectable supplement.
While we strive to always provide accurate, current, and safe advice in all of our articles and guides, it’s important to stress that they are no substitute for medical advice from a doctor or healthcare provider. You should always consult a practicing professional who can diagnose your specific case. The content we’ve included in this guide is merely meant to be informational and does not constitute medical advice.
- National Heart, Lung and Blood Institute. (n.d.). Pernicious Anemia. Retrieved from https://www.nhlbi.nih.gov/health-topics/pernicious-anemia
- Penn State Hershey. (2011). Vitamin B 12 (Cobalamin). Retrieved from http://pennstatehershey.adam.com/content.aspx?productid=107&pid=33&gid=000332