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Vitamin B12 (Cobalamin)

Vitaminoral · inferred

Essential for nerve function, DNA synthesis, and red blood cell formation. Common deficiency in vegetarians/vegans.

Projected serum levels — 1k mcg (≈ 1 mg), once daily

Vitamin B12 (Cobalamin)
Vitamin B12 (Cobalamin) modeled serum levels, 1k mcg (≈ 1 mg) once daily over 46 days Population-based pharmacokinetic estimate. Steady state reached after approximately 18 days. 0 0.25 0.50 0.75 1 Day 0 Day 12 Day 23 Day 35 Day 46 Time on a regular schedule ≈ steady state · day 18
Vitamin B12 (Cobalamin) modeled serum levels with a loading dose of 3k mcg, then 1k mcg (≈ 1 mg) once daily The first dose is larger so levels approach steady state faster. 0 0.25 0.50 0.75 1 Day 0 Day 12 Day 23 Day 35 Day 46 Time on a regular schedule

Maintenance schedule: 1k mcg (≈ 1 mg) once daily (oral).

Loading schedule: 3k mcg on day 1, then 1k mcg (≈ 1 mg) once daily — reaching therapeutic levels sooner.

Modeled steady state after ~18 days: peak ≈ 0.10 mg, trough ≈ 0.096 mg body load. Population-based estimate over 46 days for a reference dose at a 70 kg reference body mass — the interactive app scales curves to your doses, timing, and body mass.

Key facts

Category
Vitamin
Route modeled
Oral
Model confidence
inferred
Half-life
6 days
Common dose
1k mcg (≈ 1 mg)
Suggested maximum
5k mcg/day
Reference dose range
500–5k mcg (single dose)
Suggested cadence
once daily
Validated against
1 mg oral — Cmax 0.001 mg/L at 8 h

Documented interactions

  • danger
    Levothyroxine (Synthroid) + Vitamin B12 (Cobalamin) Protein binding

    Vitamin B12 (Cobalamin) may displace Levothyroxine (Synthroid) from plasma protein binding sites, transiently raising free drug concentration. This drug has a narrow therapeutic index; free…

  • warning
    Apigenin + Vitamin B12 (Cobalamin) Protein binding

    Apigenin may displace Vitamin B12 (Cobalamin) from plasma protein binding sites, transiently raising free drug concentration.

  • warning
    Aripiprazole (Abilify) + Vitamin B12 (Cobalamin) Protein binding

    Aripiprazole (Abilify) may displace Vitamin B12 (Cobalamin) from plasma protein binding sites, transiently raising free drug concentration.

  • warning
    Armour Thyroid (Desiccated Thyroid Extract) + Vitamin B12 (Cobalamin) Protein binding

    Vitamin B12 (Cobalamin) may displace Armour Thyroid (Desiccated Thyroid Extract) from plasma protein binding sites, transiently raising free drug concentration.

  • warning
    Astaxanthin + Vitamin B12 (Cobalamin) Protein binding

    Astaxanthin may displace Vitamin B12 (Cobalamin) from plasma protein binding sites, transiently raising free drug concentration.

  • warning
    Atomoxetine (Strattera) + Vitamin B12 (Cobalamin) Protein binding

    Atomoxetine (Strattera) may displace Vitamin B12 (Cobalamin) from plasma protein binding sites, transiently raising free drug concentration.

Serum checks 145 modeled interaction pairings for vitamin b12 (cobalamin) across your whole stack — absorption conflicts, enzyme inhibition, and nutrient depletion included.

Research behind this entry

  1. Vitamin B-12 supplementation improves cognitive function in elderly patients with vitamin B-12 deficiency Eussen SJ et al. · American Journal of Clinical Nutrition, 2006 DOI

    Found that oral B12 supplementation improved cognitive function in elderly individuals with documented B12 deficiency.

  2. How prevalent is vitamin B-12 deficiency among vegetarians? Pawlak R et al. · Nutrition Reviews, 2013 DOI

    Systematic review found high rates of B12 deficiency in vegetarians (up to 86.5% in certain groups), strongly supporting supplementation in plant-based diets.

  3. Vitamin B12 deficiency Stabler SP · New England Journal of Medicine, 2013 DOI

    Authoritative clinical review covering diagnosis and management of B12 deficiency, including neurological manifestations and treatment protocols.

3 published studies referenced in the app, each with a plain-language summary.