Vitamin B12 Injection
genericInjectable vitamin B12 (cyanocobalamin) is FDA-approved for treating B12 deficiency and pernicious anemia. Methylcobalamin injections from compounding pharmacies are compounded and not FDA-approved as finished products.
Est. Cost
$15 - $75/mo
Vitamin B12 (cobalamin) is an essential nutrient involved in red blood cell formation, neurological function, and DNA synthesis. B12 deficiency can cause fatigue, weakness, neurological symptoms, and anemia. While oral B12 supplements are widely available over-the-counter, injectable B12 has become popular in the telehealth and wellness space because it bypasses potential absorption issues in the gastrointestinal tract. Standard cyanocobalamin injections are FDA-approved for treating B12 deficiency. Methylcobalamin — the active form of B12 preferred by some providers — is typically available as a compounded injection and is not FDA-approved as a finished product.
Dosage Format
Standard treatment for B12 deficiency: 1,000mcg intramuscular injection daily or every other day for 1-2 weeks, then weekly for a month, then monthly maintenance. Wellness-focused protocols from telehealth providers may vary. Dosing should be determined by a licensed provider based on blood levels and clinical need.
Type
Generic
Who to discuss it with
Adults with B12 deficiency, those on plant-based diets, or individuals interested in injectable B12 for energy and neurological support
Key distinction
Vitamin B12 deficiency affects an estimated 6-20% of adults, with higher prevalence in older adults and those following plant-based diets. Injectable B12 bypasses absorption issues that can limit oral supplement effectiveness.
Where to Get Vitamin B12 Injection
Provider listings related to vitamin b12 injection. Confirm the exact formulation, current availability, and full price directly.
Hims
B12 included in biotin gummy formulation and some weight loss kits. Not offered as standalone injectable.
From $16/mo (in gummies)
Ro
B12 may be included in weight management or bundled treatment programs. Check current offerings for availability.
Included in select programs
Push Health
Consultation to request injectable B12 prescription. Medication costs separate and vary by pharmacy.
~$40/visit + medication
How Vitamin B12 Injection Works
Vitamin B12 serves as a cofactor for enzymes involved in DNA synthesis, fatty acid metabolism, and myelin production (the protective coating around nerves). When delivered via injection, B12 enters the bloodstream directly, bypassing the complex absorption pathway in the stomach and intestines that requires intrinsic factor. This makes injectable B12 particularly valuable for individuals with absorption issues (pernicious anemia, gastric surgery, certain medications) or severe deficiency. For individuals without absorption issues, oral B12 supplementation may be equally effective, though some providers and patients prefer the injectable route for its reliable delivery.
Side Effects
Common
- • Injection site pain, redness, or swelling
- • Mild diarrhea
- • Itching or skin rash (uncommon)
- • A feeling of warmth or flushing
Serious risks and warning signs
- • Allergic reaction (rare) — seek medical attention for difficulty breathing, swelling, or severe rash
- • Hypokalemia (low potassium) — can occur when treating severe deficiency as new red blood cells are formed
- • Pulmonary edema in rare cases with high-dose IV administration
Eligibility to Discuss With a Clinician
B12 injections are generally appropriate for adults with documented B12 deficiency, those at risk of deficiency (plant-based diets, older adults, those taking metformin or PPIs), or individuals with absorption issues. For those with normal B12 levels and no absorption concerns, oral supplementation may be sufficient. A provider should evaluate your B12 levels through blood work before prescribing injections.
Related Medications
Provider Reviews
Explore providers in the supplements category. This does not mean every provider offers Vitamin B12 Injection; check the exact product with the provider.