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Men/Explore care/Vitamin B12 Injection
Free lab panel at month 3Start by Jan 31
Methylcobalamin (B12) 5 mg/mL injection vial package

4.5 on Google

Vitamin B12 Injection

Injection · 5 mg/mL methylcobalamin

Low B12, fixed at the source. A weekly methylcobalamin injection that skips your gut.

$11.90/weekBilled $119 every 70 days

Start my $20 doctor visit

Medication is charged only if your clinician prescribes it.

Free lab panel with your treatment Start by Jan 31

Biological Age Reveal

Given at your 3-month mark as a progress check.

  • US clinicians
  • Licensed pharmacy
  • LegitScript
  • $20 review refunded
  • Free discreet shipping
  • A weekly injection that skips gut absorption
  • Methylcobalamin 5 mg/mL, one vial covers 70 days
  • Dose reviewed and adjusted by your clinician

70-day supply

$11.90/week

Billed $119 every 70 days · Cancel anytime

  • Injection · 5 mg/mL methylcobalamin
  • Free, discreet shipping
  • Prescribed only if appropriate

Start with a $20 clinician review

The review fee is refunded if you’re not prescribed. Medication is billed separately only if prescribed.

Start my $20 doctor visit

Prescribed only if appropriate. Compounded medications are not FDA-approved. Review the full terms in checkout.

What the research shows

  • 19.1% vs 9.5%

    had low or borderline-low B12 after 5 years on metformin vs placebo, in about 1,700 adults from a randomized trial

    Source: Aroda VR, et al. J Clin Endocrinol Metab 2016;101(4):1754-61 (Diabetes Prevention Program Outcomes Study)

  • 65% higher

    odds of B12 deficiency after 2 or more years on a proton pump inhibitor, in a study of 25,956 people with deficiency

    Source: Lam JR, et al. JAMA 2013;310(22):2435-42

  • 2 to 3%

    of US adults have a B12 deficiency, and the risk rises with age, metformin and acid-reducing drugs

    Source: Patel H, McGuirk R. Am Fam Physician 2025;112(3):294-300

Figures come from published studies of who runs low on B12. They describe the problem, not a result from our product. Ours is compounded methylcobalamin and was not studied in these trials. Individual results vary.

Methylcobalamin (B12) 5 mg/mL injection vial package

What the research measured

3.6%
Of US adults aged 19 and older fall below 200 pg/mL, the cutoff used to define deficiency in that survey
12.5%
Fall below 300 pg/mL, the level described as low or marginal status
203 to 813 pg/mL
The normal serum B12 range published by the NIH Office of Dietary Supplements

Thresholds and population figures from the NIH Office of Dietary Supplements Vitamin B12 Fact Sheet for Health Professionals, citing the National Health and Nutrition Examination Survey 2007 to 2018. ODS does not set one flat diagnostic cutoff, it notes that clinicians use values lower than 200 or 250 pg/mL, and 200 is the threshold that prevalence analysis used.

Read the source research

The Low-B12 Fix Plan

Bring a low B12 back into range with one injection a week at home, no matter what your gut or your medicines are doing to absorption.

Everything included

  • Licensed clinician review

    A US-licensed clinician reads your history, your medicines (including metformin and acid reducers) and any B12 results you share, and prescribes only if injectable B12 fits.

  • Compounded methylcobalamin, 5 mg/mL

    A 10 mL vial from a licensed US pharmacy. One fill covers 70 days at the listed directions.

  • A starting dose and a step up

    The directions begin at 2.5 mg once a week and allow 5 mg after 2 weeks if you tolerate it. Your clinician can change the plan.

  • Free, discreet shipping

    2 to 5 business days after your clinician approves a prescription.

  • Care-team messaging

    Message your care team about side effects or dose. Your clinician adjusts the plan as you go.

Bonuses

  • Free lab panel at month 3

    Biological Age Reveal, as a progress check.

  • “What if the first dose is not enough?”

    Dose step-up built in

    The prescription directions allow a move from 2.5 mg to 5 mg after 2 weeks if tolerated.

  • “Will my other medicines get in the way?”

    A medicine-aware review

    Your clinician looks at metformin, acid reducers and other medicines as possible causes, not just at the number.

Methylcobalamin (B12) 5 mg/mL injection vial package

70-day supply

$11.90/week

Billed $119 every 70 days

  • B12 injection at another online clinic, starting price on its 3-month plan (source)$65/mo
  • B12 injection at a second online clinic (source)$70/mo
  • Cyanocobalamin B12 injection at a third online clinic (source)$85/mo
  • Your plan, per month$59.50/mo
  • $20 review refunded if not prescribed
  • Cancel anytime

Free, discreet shipping

Start my $20 doctor visit

Start today: your clinician reviews within 24 hours, and your vial ships 2 to 5 business days after approval.

Labs we cover

Biological Age Reveal

  • CMP
  • CBC with differential
  • hs-CRP
  • Biological age score

Start or transfer your treatment between Nov 1 and Jan 31 and get this panel free at your 3-month mark. Labs are a bonus, not needed to start treatment.

From a low B12 to a weekly injection

B12 from food has to be freed by stomach acid, bound to a carrier called intrinsic factor, then absorbed in the last stretch of the small intestine. Metformin, acid-reducing drugs, gastritis, celiac or Crohn's disease, weight-loss surgery and age can each break a link in that chain. A weekly injection goes under the skin and never touches it.

Serum B12 is the first check. When it sits in the borderline zone, methylmalonic acid (MMA) and homocysteine show whether your cells are short, because both build up when B12 runs low. The ranges our clinicians use are stricter than the lab cutoff for deficiency: B12 above about 545 pg/mL, MMA at or below 260 nmol/L, and homocysteine of 5.0 to 7.2 umol/L.

One injection a week. Injecting skips the gut, where B12 absorption most often breaks down.

  1. 1
    Step 1
    A South Asian woman in her early 50s with a silver streak in her hair looking over her lab results at home

    Tell us what you take and how you feel

    Answer a few health questions online and share any recent B12, MMA or homocysteine results you have. Metformin and acid reducers are worth mentioning.

  2. 2
    Step 2
    Messaging the care team from home

    A licensed clinician reviews you

    They check your history and medicines and prescribe only if injectable B12 fits. Reviewed within 24 hours.

  3. 3
    Step 3
    A white woman in her late 40s with shoulder-length auburn hair on a video visit with her clinician at home

    Your vial ships from a US pharmacy

    If prescribed, a 10 mL vial of methylcobalamin ships free in discreet packaging in 2 to 5 business days.

  4. 4
    Step 4
    Clear, rested skin in natural light

    Adjust as you go

    One small injection under the skin each week. Repeat labs show whether B12 and MMA moved, and your clinician adjusts your dose.

A man stretching on a terrace overlooking the sea

What to expect

  1. 01

    Blood B12 climbs first

    Levels rise quickly after injections. How you feel depends on how low you were.

  2. 02

    If you were low

    Energy and clearer thinking may follow. Nerve symptoms such as tingling take longer to settle.

  3. 03

    If you were normal

    Expect no change. Extra B12 has not been shown to add energy when levels are adequate.

  4. 04

    Pink urine is normal

    The excess leaves in your urine and is harmless.

  5. 05

    Recheck

    Repeat B12, MMA and homocysteine show whether your cells caught up, and your clinician adjusts your dose.

What makes it work better

Three things you can do alongside your treatment.

  1. A relaxed man in a sand-colored sweater walking along a quiet tree-lined path in warm late-afternoon light.
    01

    Find out why you are low

    B12 needs stomach acid, a carrier protein and a healthy lower small intestine. Metformin, long-term acid reducers, gastritis, celiac or Crohn's disease and age each interrupt that chain. Share your medicine list, and if no cause is clear, ask about testing for H. pylori and autoimmune gastritis.

  2. Man preparing vegetables in his kitchen
    02

    Eat B12 foods as well

    B12 comes from animal foods such as clams, liver, fish, meat, poultry and eggs, plus fortified foods. If you eat mostly plants you are at higher risk, so injections work best alongside a food plan, not instead of one.

  3. A couple relaxing together outdoors
    03

    Keep folate and homocysteine in view

    Your cells need folate as well as B12 to keep homocysteine low, so greens, legumes and other folate-rich foods help. We watch B12, methylmalonic acid and homocysteine together, because one number alone can miss a shortfall.

Injection, high-dose pills or food

FeatureOur B12 injectionHigh-dose oral B12Food and a multivitamin
How it gets inUnder the skin, past the stomach and gutA small share is absorbed without the usual carrier, so doses are largeNeeds stomach acid and intrinsic factor to work
What the evidence saysInjected B12 is the long-standing treatment for poor absorption; ours is methylcobalamin, which was not the form in most trialsIn 3 small trials oral raised B12 as well as injections did (low-quality evidence); a 2025 review calls oral noninferiorWorks for keeping up, not for correcting a deficiency on its own
Best forAbsorption problems, severe deficiency, nerve symptoms, or one weekly stepMost people with a mild to moderate shortfallStaying in range once you are there
FormatOne injection a week at homeA pill every dayEveryday meals
Regulatory statusCompounded, not FDA approved; prescribed only if appropriateSupplement or prescription, depending on the productNot applicable

Your clinician decides whether an injection fits. If pills would serve you as well, they will tell you.

Before you start

  • Tell your clinician every medicine you take. Metformin and acid reducers are common reasons for low B12.
  • Do not take B12 if you are sensitive to cobalt or to vitamin B12.
  • Tell your clinician about Leber's disease, severe anemia, or low potassium. Do not use folic acid in place of B12, because it can hide anemia while nerve damage progresses.
  • Never stop a prescribed medicine on your own. If you think a drug is lowering your B12, raise it with the clinician who prescribed it.
  • Methylcobalamin here is compounded by a licensed US pharmacy and is not FDA approved. It is prescribed only if it is right for you.

How to take it

Inject 50 units (2.5 mg) subcutaneously once weekly. May increase to 100 units (5 mg) if tolerated after 2 weeks, as directed by your clinician. Discard any remaining medication.

Side effects and safety

B12 injections made as cyanocobalamin are FDA approved for B12 deficiency from poor absorption, including pernicious anemia. What we dispense is compounded methylcobalamin, which is not FDA approved. Using B12 for energy when your levels are normal is off-label.

Tell your care team straight away if you get trouble breathing, throat swelling or hives after an injection, vision changes, chest tightness or leg swelling, muscle weakness, or an irregular heartbeat.

Common side effects

  • mild diarrhea
  • itching
  • rash
  • a reaction where the injection was given

Rare but serious

  • severe allergic reactions, which have been reported after injected B12
  • low potassium and heart rhythm problems when severe anemia is treated quickly
  • fluid on the lungs early in treatment
  • rapid worsening of vision in people with an inherited eye condition called Leber's disease

Do not take this if you are sensitive to cobalt or to vitamin B12. Do not use folic acid in place of B12, because it can hide anemia while nerve damage progresses.

This is not a complete list of side effects. Message your care team about any symptom that worries you. What we dispense is a compounded preparation made by a licensed US pharmacy. Compounded medications are not approved by the FDA for safety, efficacy or quality.

Read the source research

Your questions, answered.

A man with gray hair in a cream knit sweater relaxing on a sunny terrace beside olive trees, smiling during a phone call.
Who actually benefits from B12 injections?+

People whose B12 is low or borderline. Common reasons are long-term metformin, acid-reducing drugs, age, a plant-based diet, and gut conditions such as celiac or Crohn's disease. If your levels are already normal, more B12 is unlikely to change how you feel.

I am tired. Will B12 give me energy?+

Only if low B12 is part of the reason. Reviews of the evidence find that B12 helps fatigue in people who are short on it, not in people who are replete. That is why a clinician reviews you first and why we suggest sharing any B12, MMA or homocysteine results.

Why an injection and not high-dose pills?+

For many people pills work. In 3 small trials, high-dose oral B12 raised blood levels about as well as injections, and a 2025 review calls oral noninferior for most adults. Injections are usually preferred for severe deficiency, nerve symptoms or poor absorption, and some people simply prefer one weekly step.

What is the difference between methylcobalamin and cyanocobalamin?+

Ours is methylcobalamin, one of the active forms. Approved B12 injections are cyanocobalamin, and most trials used that form. Cells convert B12 forms into the ones they need, and we are not aware of a head-to-head trial showing a clinical edge for either.

How and how often do I inject?+

The directions are 50 units (2.5 mg) under the skin once a week. After 2 weeks your clinician may raise it to 100 units (5 mg) if you tolerate it. A 10 mL vial of 5 mg/mL covers 70 days. Your clinician adjusts the plan to you.

Which labs should I look at?+

Serum B12 first. If it is borderline, methylmalonic acid (MMA) and homocysteine show whether your cells are actually short, because both rise when B12 runs low. The optimal ranges our clinicians use are B12 above about 545 pg/mL, MMA at or below 260 nmol/L and homocysteine of 5.0 to 7.2 umol/L.

Why is my urine pink afterwards?+

B12 is a deep red compound and the excess leaves in your urine. A day or so of pink urine is expected and harmless.

Is it approved, and is it safe?+

B12 injections made as cyanocobalamin are FDA approved for deficiency from poor absorption, including pernicious anemia. What we dispense is compounded methylcobalamin, which is not FDA approved or reviewed for safety, efficacy or quality. Common effects are mild diarrhea, itching, rash and soreness at the injection site. Rare serious ones include allergic reactions and low potassium when severe anemia is treated quickly.

The Low-B12 Fix Plan

  • Reviewed by a US-licensed clinician, and prescribed only if it suits you
  • Filled by a licensed US pharmacy
  • Free, discreet shipping to your door
  • LegitScript certified, and rated 4.5 on Google

70-day supply · $11.90/week · Billed $119 every 70 days

Start my $20 doctor visit
  • $20 review refunded if not prescribed
  • Cancel anytime
  • Free, discreet shipping
An East Asian woman in her early 40s with a bob opening a plain delivery box at home while talking with her clinician

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Prescription products require an online consultation with a licensed clinician who will determine if a prescription is appropriate. Individual results vary. Not for use in a medical emergency. © Vitals Vault

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$11.90/week

Billed $119 every 70 days

Start $20 visit