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Vitamin Injections: Maximizing Wellness & Countering Deficiency

Vitamin Injections: Maximizing Wellness & Countering Deficiency


To enjoy vibrant human health, it is crucial to eat, digest, and absorb nutritious food properly. For humans, certain nutrients (called vitamins) are vital for many biological processes. Some nutrients are so essential that the body makes them itself. For example, cholesterol is made in the liver because the human body will not live long without it. However, most vitamins must be taken in through the diet. Indeed, the definition of a vitamin states that the body generally can't create these essential substances in amounts that meet our needs for energy and vitality, so they "must be obtained from the diet or some synthetic source” (1). 

As Integrative Medicine doctors and holistic health practitioners, the Temecula Center for Integrative Medicine (TCIM) promotes a nutrient-dense diet to provide the best raw material for a thriving, resilient body. Unfortunately, we see many chronic health conditions driven by a combination of stress, nutrient deficiencies, genetic issues, and environmental factors. We advocate the "Five Pillars of Health," outlined in our article on the immune system, to promote actions that fortify people against damage to their systems.

Obtaining and maintaining life-giving foods in the diet is crucial to fantastic health. However, many people have digestive issues that prevent the proper breakdown and absorption of essential vitamins and minerals. This situation can become a catch-22 because a lack of nutrients can decrease the amount of nutrients absorbed, creating a domino effect of negative health outcomes - especially chronic illnesses. In such cases, TCIM promotes supplementing nutrients through various means, including vitamin injections.

Gut Issues: Limits of Diet and Oral Supplements

Odds are, an average diet will need supplementation because the food eaten lacks a strong enough concentration of nutrients, including vitamin B12, folate (vitamin B9), and iodine (2). Vitamins can be supplemented through food, oral nutritional supplements (liquid, capsules, tablets, or gelcaps), sublingually (lozenge), vitamin injections, or intravenous (IV) administration. 

Most people are familiar with oral nutritional supplements, as they are widely available. When a vitamin deficiency is found, a doctor may suggest oral vitamin therapy to rectify the deficiency. Unfortunately, so many people have digestive and absorption issues that there is no guarantee that oral vitamins will get absorbed properly. Some people don't even know they have malabsorption issues; they just know they feel run down all the time.

Certain health conditions are known to produce digestive or malabsorption issues such as (3):

  • Diseases involving inflammation: inflammatory bowel disease (IBD), ulcerative colitis (UC), Crohn's Disease 

  • Diseases involving autoimmunity: Celiac Disease, Crohn's Disease

  • Alcohol abuse disorder

  • Side effects of cancer therapies - radiation, chemotherapy

  • Small intestinal bacterial overgrowth (SIBO)

  • Intestinal Permeability (Leaky Gut)

Many other health conditions or even medications can damage the small intestine or affect the strength of stomach acid. For example, stomach acid-reducing medication can reduce stomach acid so much that foods aren't being properly broken down, creating a condition called hypochlorhydria (insufficient stomach acid).

The Need to Work Around the Digestive Tract

Because there are so many who have digestion and absorption issues, the popularity of intramuscular (IM) injections, subcutaneous (SC) injections, and intravenous (IV) administration of nutrients has risen tremendously in the last decade. These three routes of administration, IM, SC, and IV, all bypass the digestive system and go directly into the body. These methods of getting substances in the body allow those who suffer from digestive issues to get nutrients they otherwise would be unable to get (because they can't break down or absorb them). This dynamic is especially true in cases of vitamin B12. Vitamin B12 is necessary to maintain the gut lining where nutrients are absorbed. If this gut lining is compromised, it will not absorb vitamin B12 well, though it needs B12 to heal. So, it can become necessary to get B12 into the system without relying on the gut lining.

Efficiently Providing Nutrients: Intramuscular (IM) and Intravenous (IV) Administration

The best method of getting nutrients into the human body varies by what nutrient (or substance) it is. Some nutrients are better absorbed intravenously (IV) versus intramuscularly (IM). IV administration means the substances go straight into circulation through a vein and are used up rapidly. An IV treatment can take from 30 minutes to a few hours. IM administration means the substance gets put into a muscle using a needle and syringe, which can be done very quickly. Certain muscles act as a reservoir, slowly releasing the injected substance over time. 

Before a nutrient or supplement is placed on the market, testing is typically done to see which routes of administration work for different goals that supplementation might achieve. When a substance or nutrient can have more than one route of administration, a doctor may suggest one method over another based on patient preference, toleration, and/or medical history. 

Commonly Injected Nutrients

Some vitamins and nutrients are ideally suited for administration by injection and are now routinely administered to patients as therapy. Below is a brief review of commonly injected nutrients that we offer at TCIM.


Glutathione is an amino acid (a type of protein), a natural element in every human cell. The liver can make glutathione, which is involved in creating DNA, reducing cell-damaging free radicals, helping built-up mercury leave the brain, aiding the liver and gallbladder with fat management, and assisting the immune system (18). Glutathione can also be synthesized in large quantities for nutrient supplementation, which is helpful because certain medications can reduce glutathione levels, and acetaminophen overdose can deplete it to dangerously low levels. A master antioxidant, glutathione is used all over the body. Glutathione can be administered in multiple ways, including IM injection.

Conditions associated with glutathione depletion/deficiency: systemic inflammatory response syndrome, acute respiratory distress syndrome, chronic lung disease, chronic obstructive pulmonary disease (COPD), neurodegenerative disease, cardiovascular disease, alcoholism, infectious disease (e.g., HIV-1 infection and chronic hepatitis), hepatic and renal failure, diabetes, malnutrition, and certain autoimmune diseases (19).


The B vitamins help convert food molecules to energy that the body can use (4). Most B vitamins are absorbed in the small intestine (from broken-down food heading to the large intestine), and some small amounts of B12 are stored in the liver. B vitamins are water-soluble, making them good candidates for injections. Studied rigorously since the 1950s, B vitamin injections have been used for decades to counter deficiencies. Unfortunately, the body doesn't have an excellent storage mechanism for all the B vitamins, so it is important to get a regular intake through diet or supplementation.

1. Vitamin B12 (Cobalamin)

Vitamin B12 has a significant cobalt content, so it is called cobalamin. Meat and dairy products are significant dietary sources of vitamin B12. This vitamin plays many vital roles in the human body, such as the proper formation of red blood cells and DNA, which provide fundamental processes! Brain health, good memory, and combating cognitive decline (dementia) also depend on vitamin B12. Without this vitamin, human bodies could not extract energy from food or have healthy eyesight (5).

Vitamin B12 deficiency is quite common and can be caused by (6-9):

  • Lack of foods high in B12, such as dairy and meat (affects vegans and strict vegetarians 

  • Lack of intrinsic factor, a substance needed for absorption of vitamin B12 (pernicious anemia)

  • Impaired ability to absorb foods properly due to aging 

  • Having certain health conditions that affect the breakdown or absorption of nutrients, such as Crohn's or Celiac Disease and low or weak stomach acid (hypochlorhydria)

  • Having had gastric bypass surgery, which reduces stomach functionality because it reduces the stomach size

  • Particular medications can reduce levels of vitamin B12 in the body, such as birth control pills and drugs used to control diabetes or acid reflux. 

  • Excessive alcohol consumption can damage digestion, causing B12 and B1 (thiamine) deficiency due to decreased absorption

Vitamin B12 deficiency symptoms include extreme fatigue or weakness, stomach upset (nausea, vomiting, or diarrhea), lack of appetite or weight loss, hands or feet tingling or getting numb frequently, poor memory or getting confused easily, problems when attempting to walk or speak, mental depression, or irritability (6).

Studies have proven multiple vitamin B12 benefits, including less fatigue, reduction of muscle weakness, and reduced depression and irritability (10).

There are two main forms of B12 used in vitamin therapy injections: methylcobalamin and hydroxocobalamin. 

Methylcobalamin: This active form of vitamin B12 affects mood because it helps in the creation of serotonin and dopamine, two chemical messengers used in nerve communication. It can help correct the effects of the genetic mutation called MTHFR (among other methylation mutations), which can result in fatigue. Because this form of the vitamin is already activated, the body can use it right away. However, its ability to be rapidly used can result in temporary restlessness or anxiety in people who do not have MTHFR mutations or who are sensitive to it.

Hydroxocobalamin: This form of vitamin B12 is a precursor - the body converts it to the active form as needed. It is less likely than methylcobalamin to cause overstimulation in sensitive people. 

2. Vitamin B9 (Folate)

Vitamin B9, also known as folate, helps the nervous system form in the developing fetus, so it is often supplemented in pregnancy. Folate is so important that early miscarriage is associated with folate deficiency - the human fetus simply can't form correctly without it. Folate is crucial to the creation of RNA and DNA (12)! Lack of this vital nutrient can also lead to megaloblastic anemia, a condition where a person develops extraordinarily large (but immature) red blood cells (11). Red blood cells carry oxygen, so anemia starves tissues of oxygen and affects energy levels. 

There are many forms of vitamin B9, which causes confusion. Here's a brief explanation of the most popular forms, which have multiple routes of administration:

Folate: This is the natural form of B9 that is present in foods. The body breaks it down and converts part of it to an active form that can do work in the body.

Folic Acid: This form is an inactive synthetic, oxidized, and water-soluble form of folate (vitamin B9), which is used therapeutically but does not exist in nature (13). Those with MTHFR genetic mutations have difficulty converting this form.

Folinic Acid: Folinic acid is a breakdown product of folate that occurs naturally in the body and can be synthesized so it can be put in a supplement. It's an active form of B9, and the body can use it without any need to convert it. Those with MTHFR genetic mutations can use this form (13).

Methylfolate, methyltetrahydrofolate, methylenetetrahydrofolate, L-5-Methyltetrahydrolfolate: These are already-activated forms of vitamin B9, which are naturally created by the body in the breakdown of folate (the folate cycle) and also synthesized for supplements. These forms are also appropriate for those with MTHFR genetic mutations (12).

Folate deficiency symptoms include anemia, diarrhea, loss of appetite, weight loss, weakness, sore tongue, headaches, heart palpitations, irritability, and behavioral disorders (12), megaloblastic anemia, and increased risk of neural tube defect-affected pregnancies (14)

3. Vitamin B6 (Pyridoxine)

The human body can't make vitamin B6 and must get it from foods such as beef, fish, eggs, seeds, nuts, and whole grains. This nutrient is involved in over one hundred chemical reactions in the body, and like other B vitamins, it helps form DNA, red blood cells, and chemical messengers (15). B6 vitamin supplementation can counter depression, difficulties with the thought process, and pain or numbness in the feet or hands (16). Vitamin B6 has also been used to counter anemia, boost mood, promote heart health, reduce the risk of cancer, and lower the risk of age-related macular degeneration (an eye condition that negatively affects sight) (15).

Pyridoxine is a form of vitamin B6 that naturally occurs in foods. The active form of vitamin B6 is Pyridoxal Phosphate (P5P), which is created naturally in the body. It can also be man-made and administered via multiple routes, including IM injections.

Vitamin B6 deficiency symptoms include mental effects such as increased irritability, frequent confusion, and depression, as well as reduced brain health in general, and inflammation (15).

4. Vitamin B Blends or B-Complexes

Mixing multiple B vitamins in one shot can be helpful. Many health conditions such as migraines, anxiety, depression, and premenstrual syndrome (PMS) benefit from having various types of B vitamins administered simultaneously (17). Vitamin B complexes have been very beneficial for those with unexplained fatigue, muscle aches, and mild depression. 

TCIM offers a Quad vitamin injection, which combines B-complex, P5P, folinic acid, and methylcobalamin or hydroxocobalamin.


Injectable B Vitamins and glutathione in correct dosages have very high safety profiles, but there are rare cases of mild allergy or sensitivity (20). Receiving vitamin injections at a medical facility ensures high safety standards and has the added benefit of having multiple professionals nearby and protocols for responding to an adverse reaction.

Much of the safety aspect depends on the vitamin being injected, the dosage administered, and the individual chemistry of the person receiving the therapy.

Working with a doctor (who can review your medical and family history and determine proper dosing) decreases the risk of an unexpected adverse reaction. Injections are not generally suggested for those who faint during blood draws or have an aversion to various medical procedures.

Some vitamins, including B vitamins, may interfere with particular medications. For those on multiple medications, heart medications, blood thinners, and acid-reducing medications, having a checkup before getting vitamin injections is strongly recommended so the doctor can determine if there are any conflicts.


Vitamin injections are a convenient and potent way to bypass the digestive system and deliver a direct dose of essential vitamins and nutrients straight into your bloodstream. We offer a variety of personalized vitamin injection options to address your specific needs, and our expert staff will work with you to create a customized plan that delivers optimal results.

When a person gets the proper nutrients in the body, fantastic health recoveries are possible. If you suspect you are not absorbing nutrients properly or are suffering from a poor diet, please come in for an evaluation. There may be some easy remedies that revitalize and energize you!


Jonathan Vellinga, M.D.

Jonathan Vellinga, MD is an Internal Medicine practitioner with a broad interest in medicine. He graduated Summa cum laude from Weber State University in Clinical Laboratory Sciences and completed his medical degree from the Medical College of Wisconsin.​

Upon graduation from medical school, he completed his Internal Medicine residency at the University of Michigan. Dr. Vellinga is board-certified with the American Board of Internal Medicine and a member of the Institute for Functional Medicine.




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