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IV Vitamin Therapy: What Is It, and Does Research Back Its Benefits?

Your Complete Guide to Intravenous Vitamin Therapy

It’s become quite popular for nutrients such as vitamins, antioxidants and minerals to be given intravenously or by injection. In particular some big claims are being made for IV vitamin therapy treatment on the internet.

The treatment is said to include a boost to energy and alertness, rapid hydration and the ability to quickly get high doses of vitamins and antioxidants. But getting nutrients this way isn’t the norm, so it’s important to take a really objective look at this therapy.

In fact intramuscular treatment with B12 has been found quite unnecessary in most cases, with a higher oral dose (inexpensive and non-invasive) working just as well.

In this article, we’ll dig into the scientific evidence to see what it tells us about nutrition delivered by a drip. 

IV vitamin therapy: person adjusting an IV

What Is IV Therapy?

Intravenous (IV) therapy is an essential technique that delivers hydration, medications, and, sometimes, nutrients directly into a patient’s vein. Medical professionals use IV lines (IV drips) to deliver blood transfusions and fluids in life-threatening situations.

However, another type of intravenous procedure, often referred to as IV vitamin therapy, involves being hooked to a drip for general health benefits and as a wellness treatment. In this type of intravenous therapy, you’ll typically be given a vitamin drip that contains a specific blend of vitamins, antioxidants and electrolytes. You’ll relax while a catheter is placed in your arm. Treatment is infused into your arm over an hour or so.

Nutrition Support Therapy

IV vitamin therapy is distinct from the nutritional support therapy that some patients need during illness or after surgery, when they can’t consume enough food themselves, or their digestive system is shut down. In this case, nutrition will usually be given through a feeding tube down the esophagus into the stomach (enteral route). However, if the digestive tract isn’t functioning, nutrients can be fed through an intravenous tube into a vein (parenteral nutrition) [1].

Vitamin Injections

It’s also popular to give vitamins, particularly vitamin B12, as an intramuscular injection. Though this isn’t IV vitamin therapy, it’s fair to include it in the same category because in both cases the vitamin is administered via a needle and not taken orally.

This at-a-glance table shows the different types of non-standard (not via the mouth) nutrition:

DescriptionMedically Necessary?
Enteral nutritionLiquid food (milkshake consistency) given via a tube into the stomach.Yes in advanced or critical illness. Also useful, temporarily, in some Crohn’s patients [2, 3].
Parenteral nutritionComplete liquid nutrition (amino acids, sugars, fats, vitamins, minerals etc.) given intravenously.Yes as a life-sustaining option when there is digestive system failure [4].
IV vitamin therapyVitamin C, B complex, antioxidants (e.g. selenium, glutathione), etc., infused into a vein, along with fluid.Usually no — this is mainly a lifestyle choice [5]. However, IV iron may be given under medical advice to people who are very anemic [6].
Vitamin injectionsNutrients, e.g., vitamin B12, magnesium, vitamin D injected into the muscle.Rarely. Higher dose oral vitamins are often as effective [7, 8].

Does IV Vitamin Therapy Work?

IV vitamin therapy: person holding a saline back with fruits inside

The claims made for IV vitamin infusions include boosting the immune system, increasing mental clarity, and fighting conditions such as fibromyalgia and chronic fatigue. 

Many people swear by IV vitamin therapy. Commonly, people report feeling an immediate boost to energy levels after the treatment.

If you were deficient in one or more of the nutrients that were infused into your bloodstream, this could make sense. And if you were mildly dehydrated to start with, the rehydration you get through the fluids in the IV drip may also perk you up [5].

The Placebo Effect

Expensive and invasive treatments like IV vitamin therapy are very likely to elicit a strong placebo response. We all like to think we couldn’t be “fooled” by the placebo effect, but science says otherwise. This might especially be the case when you’ve paid a lot of money to sit hooked up to an IV that you’ve assured yourself will make you feel better! 

In fact, one study specifically noted a strong placebo effect when 34 patients with fibromyalgia received either the “Myer’s cocktail” — a specific intravenous infusion of magnesium, calcium, vitamin C, and B vitamins invented by John Myers, MD in 1959 — or a placebo IV drip [9].

The researchers found the fibromyalgia patients reported less tender points when they were injected with the Myers cocktail. However, patients injected with a placebo cocktail also reported the same benefit.

While there’s no major problem with the placebo effect in general, IV vitamin therapy shouldn’t be undertaken lightly. You could end up spending money you don’t need on a procedure that can be uncomfortable, time-consuming and even potentially harmful.

IV Vitamin Therapy Research 

Of course, benefits can go beyond a placebo effect and anecdotal reports of health benefits. In some situations IV vitamins can be the right choice, but this does tend to be for very specific medical reasons.

The tables below summarize available scientific studies on IV vitamin therapy for health and wellness reasons (both those finding no benefit and those finding moderate benefit). 

It’s also worth noting that most studies on IV vitamin therapy compare the treatment to a placebo. So, when patients do see a benefit, it’s hard to know how much of that benefit is coming from the treatment method (IV therapy) and how much is simply a result of increasing nutrient intake (which could potentially be achieved via high dose oral supplementation).

Largely Positive Studies

Type of IV Therapy / ConditionResearch DescriptionQuality of Evidence
IV magnesium for asthma A systematic review/meta-analysis (SR/MA) of randomized controlled trials (RCTs) found that IV magnesium significantly improved respiratory function and reduced hospitalization by 45% [10].Good
IV vitamin C for inflammationAn SR/MA of RCTs identified some evidence of a link between IV vitamin C and lowering of high CRP (an inflammation marker) in people under 60 [11].Good
IV vitamin C for fatigueAn RCT of healthy office workers found (compared to placebo), that those who received IV vitamin C had lower fatigue scores two hours later and lower levels of oxidation (which stresses cells) for a day [12].Moderate
IV glutathione for heart attacksAn RCT found that, compared to placebo, IV glutathione (an antioxidant) reduced levels of hydrogen peroxide after a major heart attack, improving heart cell survival [13].Moderate

Largely Negative Studies

Type of IV Therapy / ConditionResearch DescriptionQuality of Evidence
IV selenium and ARDSA small RCT of patients with acute respiratory distress syndrome found those who received IV selenium for 10 days had no better overall survival, despite some decrease in inflammatory chemicals in the lungs [14].Poor to moderate
IV vitamin C for cancerA systematic review of 34 studies (half observational studies) found that high-dose oral or intravenous vitamin C did not lead to significant improvements in overall survival from or progression of cancer [15].Moderate
IV vitamin C for sepsisAn SR/MA of mainly RCTs found that patients with sepsis who got treated with IV vitamin C were no less likely to die [16].Good
IV vitamin C for critically ill ICU patientsAn SR/MA of RCTs found that IV or oral vitamin C was not associated with a lower risk of mortality, nor did it affect infections or length of ICU stays [17].Good
IV magnesium for muscle crampsAn SR/MA of RCTs suggested that both oral and intravenous magnesium supplementation likely don’t provide clinically significant relief of muscle cramps for older adults [18].Good
IV magnesium for strokeAn SR/MA of RCTs found that IV magnesium was no better than a placebo at improving physical function, overall outcome, or mortality 90 days after having a stroke [19].Good

Consuming Nutrients Is Usually Better

Health meal with chicken, quinoa, and vegetables

IV vitamin therapy is often thought to be better because you avoid having to digest nutrients (they are delivered straight to your bloodstream instead).

But in the majority of cases, it’s much better to focus on getting your nutrients through food — we need the whole package of nutrients that a balanced whole food diet provides.

Indeed, for the vast majority of people, the healthier and safer alternative to getting vitamin shots is to drink plenty of water and take in nutrients through their diet, because the gut is the natural mode of vitamin/mineral absorption [20].

The Case of Vitamin B12

Research shows that oral nutrients can still be the better choice, even in cases where people have a proven difficulty in absorbing a particular nutrient such as vitamin B12.

This often surprises my patients — for years, it was common practice to give intramuscular vitamin B12 injections to people who tested positive for specific antibodies, known as intrinsic factor antibodies. This was because in mechanistic (theoretical) studies, these antibodies had been clearly shown to make B12 absorption harder.

Now, however, we have better data from controlled clinical trials studies that overrule the mechanistic research. Instead of needing to use intramuscular vitamin B12 (expensive and invasive), these studies show you can simply use a higher dose of oral B12 and get the same result for less outlay and much less inconvenience [7, 21, 22, 23].

This also illustrates a general principle that we’ve found to be enormously helpful in the clinic — while lab testing can be useful as a diagnostic tool, it’s not the be-all-and-end-all and should not prescribe a rigid course of action. What really matters for patients is the outcomes they experience.

Potential Harm From IV Vitamin Therapy 

Most times, having an IV vitamin infusion won’t cause any problems, as long as you are hooked up to the IV drip in clean conditions and have the needle inserted by a trained professional such as a registered nurse or paramedic.

But side effects can happen, and you should be aware of the possibility. Injecting nutrients straight into the bloodstream bypasses the normal filters of the stomach and intestines, so nutrient levels can rise much higher. 

For example, vitamin C concentrations in the body are usually tightly controlled by intestinal absorption. Increasing the daily oral dose of vitamin C by more than 10 times, from 200 mg to 2,500 mg, only increases the blood concentration by 25% (from 12 mg/L to 15 mg/L [24]. However, when vitamin C is infused into a vein, vitamin C concentration in tissues can reach about 200 times higher than that from the same dose given orally [25].

Some may argue that mega-dosing nutrients more easily is the exact point of IV vitamin therapy. However, while there is still little evidence of health benefits, I’d urge caution.

There can be specific dangers for some people, like those who have:

  • Kidney disease
  • Renal failure
  • Congestive heart failure
  • High blood pressure

In these conditions, there is a risk of fluid overload. Potassium-containing IV vitamin therapy could also lead to a heart attack in those with poorly functioning kidneys, as these patients may be unable to clear this mineral from the body quickly enough [20, 26, 27].

Safely Getting Nutrients When Your Gut Is Unhealthy

Even if you have gut issues, the principle stands that consuming nutrients is best in the majority of cases. Basically, as long as you still have a functioning digestive system (ie, can chew and swallow food), there will usually be a way to get the nutrients you need.

For some people with a currently very sensitive gut and digestive issues, this may mean following an elemental diet for a while. Elemental diets are in liquid form and contain nutrients that are predigested. Research shows that they work very well for soothing symptoms of conditions like IBS, SIBO, and Crohn’s disease [28, 29].

In other cases (when digestive issues cause absorption problems), high-dose supplements will work as well as IV or intramuscular vitamins, as we’ve already outlined above.

The Bottom Line

When you dig into the research, there’s little scientific evidence to support IV vitamin therapy for most people. Investing in a good clean whole-food diet and appropriate supplements, should you need them, is likely a much safer route.

My book Healthy Gut, Healthy You gives more details on how to eat healthily and use supplements, especially probiotics, for better gut and all-round health. For specific health problems that need more personalized support, you could also consider signing up for an in person or virtual consultation.

➕ References

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