NAD Shots vs B12 Shots: Two Energy Injections With Different Jobs

For adults whose B12 is already normal, NAD shots are the better fit. NIH’s Office of Dietary Supplements says extra B12 does not provide energy benefits when you get enough (NIH ODS). NAD+ is a coenzyme every cell uses to turn food into energy, and Arbor’s clinicians prescribe it in a longevity program with medical oversight. Human evidence for injected NAD+ is early, so the program supports your levels rather than promising a specific result.

If a blood test shows low vitamin B12, B12 shots are the right call, and NAD+ is not a substitute. Cyanocobalamin injection is FDA-approved for B12 deficiency caused by poor absorption, including pernicious anemia (DailyMed label).

The table sets out NAD vs B12 on the points that usually decide it. One is a vitamin with an approved medical use. The other is a coenzyme prescribed as wellness support.

Scroll the table sideways to see both columns →

The difference between them starts with what is in the syringe.

What each shot contains

Most B12 injections contain cyanocobalamin, a form of vitamin B12 the body converts into its active forms, methylcobalamin and 5-deoxyadenosylcobalamin (NIH ODS). A cyanocobalamin injection is a prescription drug given into a muscle or under the skin. A methylcobalamin injection delivers an active form directly, but it is compounded rather than approved.

Inside each NAD+ shot is nicotinamide adenine dinucleotide, the coenzyme itself. It is neither a vitamin nor a peptide. The NAD+ shots compared here are compounded by a licensed U.S. pharmacy and given as a small injection under the skin at home.

How each one works in the body

Vitamin B12 is needed for red blood cells, nerves and DNA. Without it, red blood cells form abnormally, a condition called megaloblastic anemia, and nerves can be damaged (NIH ODS).

NAD+ is the main active form of niacin, vitamin B3, and more than 400 enzymes require it. Its main job is in the reactions that move energy from food into ATP, the cell’s fuel (NIH ODS). That role is the basis for the NAD shots benefits people hope for. A companion guide to what the NAD+ evidence supports grades each claim. Most human data come from oral precursors, not injections.

Who each shot is for, including B12 deficiency

B12 shots are for people with a diagnosed or likely deficiency. The injection treats a shortfall from pernicious anemia, conditions or medicines that block absorption, or a strict vegan diet. NIH also flags older adults, digestive disorders, digestive surgery, and long-term metformin or acid-reducing drugs. Deficiency affects between 3% and 43% of older adults, and a blood test can check your level (NIH ODS).

For NAD+, the fit is adults with nothing to correct who want a medically guided approach to energy and healthy aging.

What the evidence shows for each

For deficiency, the label calls injected B12 the recommended treatment for pernicious anemia, needed for life. A Cochrane review found low-quality evidence that high-dose oral B12 can normalize blood levels about as well as injections (Cochrane, 2018). Claimed B12 shot benefits outside a deficiency are another matter: NIH says B12 does not appear to improve athletic performance or endurance when your levels are sufficient.

For NAD+, the human evidence is early. A 2026 systematic review of 113 studies, 33 of them in people, found oral precursors reliably raise NAD+ markers, with mixed and often absent effects on function. It found no outcome trials of intramuscular or intravenous NAD+ for wellness (Ageing Res Rev, 2026). In a 2019 pilot, plasma NAD+ did not rise for the first 2 hours of a 6-hour infusion (Front Aging Neurosci, 2019).

Cost & how often each is given

The MedlinePlus vitamin B12 shot facts describe a typical schedule for deficiency: a shot daily for the first 6 to 7 days, then every other day, then every 3 to 4 days, and finally once a month, for some people for life, usually in an office or clinic. Prices vary by pharmacy, clinic and insurance, so ask for the total, visits included.

Arbor’s NAD+ program starts at $99 a month, one monthly price with the medication, physician review and check-ins included. You inject it at home on a schedule your clinician sets, and the explainer on what NAD therapy involves covers what to expect.

Prescription & FDA status

A cyanocobalamin injection is an FDA-approved prescription drug for B12 deficiency caused by malabsorption (Drugs@FDA). Drugs@FDA lists no approved methylcobalamin product. Methylcobalamin sits in Category 1 of FDA’s 503A bulk substances, the ones still under evaluation for compounding, and with no approved product, its injections are compounded drugs (FDA 503A categories).

NAD+ is in that same Category 1. Compounded NAD+ is not FDA-approved, and FDA does not verify the safety, effectiveness or quality of compounded drugs before they are marketed (FDA). Both shots need a prescription.

The first question is simple: is there a deficiency to correct? A B12 deficiency is diagnosed with a blood test, and when it is present, B12 is the treatment. NAD+ does not replace it.

B12 may fit better when:

• A blood test shows low B12, or your clinician suspects a deficiency
• You have pernicious anemia, a digestive condition or past stomach or bowel surgery that limits absorption
• You eat a strict vegan diet or take metformin or acid reducers long term, and your level is low

NAD+ may fit better when:

• Your B12 is normal and you want a clinician-guided longevity program
• You want a physician to review your history and set the dose
• You prefer a small injection at home, with licensed clinicians available 24/7

Arbor’s NAD+ shots are prescribed only after a physician reviews your intake. Still, NAD+ shots are not for everyone: pregnancy, breastfeeding, a cancer history and your current medicines all belong in that review. For B12, the label lists sensitivity to cobalt or vitamin B12 as a reason not to use it and warns about early Leber’s hereditary optic neuropathy. If it is not the right fit, it is not prescribed.

B12 injections correct a deficiency, and for that job they are the approved, proven choice. NAD+ injections do a different job: clinician-guided support for cellular energy metabolism in adults who are not deficient, on early human evidence.

Start with a B12 test if a deficiency is possible. If your levels are normal and you want medical oversight, NAD+ is the option Arbor’s clinicians can prescribe. Weighing capsules too? Compare NAD+ injections vs NMN supplements first.