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A practitioner wearing medical gloves prepares a b12 injection.

B12 injections work quickly and typically show noticeable effects within 48 to 72 hours. These effects may include better moods, more energy, less fatigue, and a general sense of wellbeing.

If you have a mild deficiency, it may take two to three shots over several days or weeks before you begin feeling a difference. For severe deficiencies, it can take even longer, since your vitamin stores are extremely depleted.

B12 shots are one of the most effective forms of supplementation, because all of the vitamin is delivered into the bloodstream. Oral supplements pass through the digestive tract to be absorbed by the bloodstream, and much of the nutrient is lost in this process. People with digestive issues may struggle to absorb oral supplements at all.

The effectiveness of vitamin injections is why B12 shots are often prescribed for deficiencies.

What is a B12 Shot?

A B12 shot, or vitamin B12 injection, delivers B12 directly into the bloodstream.

B12 shots are available in multiple forms, including cyanocobalamin, which is the synthetic version, and methylcobalamin, which is a naturally occurring form. Methylcobalamin is absorbed more effectively by the body and is therefore considered the better option.

B12 shots are recommended for individuals with a potential B12 deficiency, as well as individuals who feel they need additional nutritional support—especially when oral supplements are not effective.

Factors that can increase the risk of B12 deficiency include being over the age of 75, digestive absorption issues, autoimmune conditions, and certain diets like vegetarianism and veganism.

Because most of the B12 in our diet comes from animal products, vegan eaters are especially at risk of developing a B12 deficiency.

B12 shots may help restore healthy red blood cells, alleviate symptoms like fatigue and weakness, and offer faster benefits compared to oral vitamins.

What Does B12 Do in the Body?

Vitamin B12 is crucial for many bodily functions. It’s responsible for forming red blood cells, white blood cells, and platelets, all of which are very important for overall health.

B12 is also involved in the process of creating DNA, along with brain and nerve cells. It plays a role in the production of the neurotransmitters serotonin and dopamine, as well, which is why it can strongly impact mood.

B12 also helps the body convert food into energy. A deficiency in B12 can lead to a significant decrease in energy and exercise tolerance, along with fatigue.

B12 occurs naturally in meats, dairy, fish, and other animal products. Our bodies don’t create it, meaning we have to receive it from diet or supplementation.

What Are the Benefits of B12 Shots?

Because of B12’s multiple functions within the body, supplementation can lead to many benefits.

Patients often take B12 shots to improve their mood and energy levels, since B12 supports the production of serotonin and dopamine and encourages the conversion of food to energy.

Many patients report that regular B12 supplementation gives them an increased sense of wellbeing. B12 can also be a useful addition to a weight loss plan, because it can provide the energy needed to maintain regular exercise.

B12 can help with fatigue related to anemia due to its blood-building benefits, as well. If you have a B12 deficiency, that’s likely the cause for your anemia in the first place.

Where Can I Buy B12 Shots?

Defy Medical offers B12 shots on-site at our clinic in Tampa, Florida.

You can combine your B12 shot with other injections and IV infusions offered at our clinic to provide additional nutritional support and hydration. Our trained clinic staff will perform these injections and infusions for you in a comfortable environment.

You can also order B12 shots online through Defy Medical’s convenient patient portal and administer the injections yourself.

We offer one-on-one support to walk you through your injection, plus detailed instructions on how to inject correctly. You can purchase necessary injection materials like syringes, alcohol wipes, and sharps containers via our Patient Portal, as well.

Are B12 Shots Safe?

B12 shots are considered safe for most individuals.

There are no reported risks associated with large doses of B12, since the vitamin is water soluble and excess amounts are flushed out of the system.

Some contraindications (reasons not to take B12 shots) include:

  • Allergies to cyanocobalamin or methylcobalamin
  • Kidney or liver disease
  • Eye issues, especially if you have Leber’s disease
  • A current infection
  • If you’re taking medication related to bone marrow

You should talk to your doctor about the above conditions before getting B12 injections. You should also check with a medical provider prior to getting B12 injections if you are pregnant or breastfeeding.

How Much B12 Should Be Included in a Shot?

Your dosage should be determined by a healthcare professional based on your needs.

The dosing instructions will depend on a number of factors, including whether you have a deficiency, your age, your overall health, and any underlying conditions that should be considered.

A common protocol for patients with a B12 deficiency may be 1,000 mcg daily for one week, then the same dosage once weekly,  and then the same dosage once per month after the deficiency has been addressed.

Patients who don’t have a deficiency but are looking to optimize their B12 levels may utilize weekly or monthly injections depending on their response to treatment.

What Is the Difference Between B12 Shots and B12 Oral Supplements?

Injectable B12 delivers the vitamin directly into the bloodstream, allowing for immediate absorption. Oral supplements, on the other hand, require ingestion and absorption through the digestive system.

While injectable B12 is generally considered more effective, oral supplements are an acceptable alternative depending on the needs of the patient.

Factors such as convenience, cost savings, potential digestive absorption issues, and comfort with self-administering injections can influence patients’ preferences.

B12 Shots with Defy Medical

Defy Medical offers access to B12 shots along with a wide range of high-quality supplements. You can access on-demand blood testing to check for vitamin deficiencies and order supplements from Defy Medical’s online patient portal.

If you decide to order injectable nutrition, you can purchase necessary supplies like syringes and sharps containers. Defy Medical will provide guidance on how to administer your B12 shots, as well.

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