Label arithmetic · NIH DSLD 309690
Geri-Care Magnesium Oxide 400 mg: 240 mg of magnesium per tablet, 1–2 tablets a day
240 mg of magnesium per tablet; the label's 1–2 tablets a day give 240–480 mg. No US price matched (Nov 2). Inside: salt weight, %DV check.
Geri-Care Magnesium Oxide 400 mg declares 480 mg of elemental magnesium per serving as oxide, which means 796 mg of magnesium oxide pressed into 1–2 tablets, compared with 1,100 mg in the largest standard capsule; capsule verdicts do not apply to a tablet. No US retail price matched as of 2026-11-02; 10 of the 61 oxide labels in this registry have a matched price. NIH DSLD 309690, label dated 2024-06-20.
computed from the filed label
Chart data
| Displayed chart text |
|---|
| gluconate |
| 8,191 |
| orotate |
| 6,602 |
| L-threonate |
| 5,818 |
| taurate |
| 5,381 |
| lactate |
| 3,997 |
| glycerophosphate |
| 3,840 |
| glycinate |
| 3,404 |
| malate |
| 3,089 |
| aspartate |
| 3,069 |
| citrate |
| 2,970 |
| sulfate |
| 2,377 |
| chloride |
| 1,880 |
| carbonate |
| 1,665 |
| hydroxide |
| 1,152 |
| oxide |
| 796 |
Data release 2026-08-10-f441aa9f · registry snapshot 2026-08-10 · latest price observation 2026-10-19 · chemistry 2026-10-17
Mass: 398 mg per tablet · Price: none matched · % DV: 114% vs 114%
Elemental: The magnesium itself; the rest of the compound weight is the partner molecule.
Compound: The whole salt, such as magnesium glycinate, that must physically fit in the capsule.
Size 000: The largest standard capsule, about 1,100 mg of powder at 0.8 g/mL, the top of the usual 0.6–0.8 range; size 00 holds about 730 mg and size 0 about 545 mg.
Recompute with your price
Enter the price you paid; the declared amount and servings of this label are prefilled, so the result is the cost per 100 mg of elemental magnesium for your bottle.
Same-salt comparison appears here.
How much oxide is pressed into one tablet?
Geri-Care Magnesium Oxide 400 mg carries 796 mg of magnesium oxide per serving for 480 mg of elemental magnesium, against 1,100 mg in the largest standard capsule; capsule capacities do not apply to this tablet or pill.
computed with assumption| Measure | Value |
|---|---|
| Elemental magnesium per serving | 480 mg |
| Units per serving | 1–2 |
| Magnesium oxide per serving | 796 mg |
| Magnesium oxide per tablet | 398 mg |
| Capsule capacity 0 · 00 · 000 | 545 · 730 · 1,100 mg |
| Verdict | Capsule sizes do not apply |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does the label's own text add up on magnesium?
The label's own text says “400 mg Magnesium Oxide, equivalent to approximately 240 mg of elemental Magnesium”: 240 mg of magnesium from 400 mg of magnesium oxide is 60.0% magnesium, against the 60.3–60.3% that magnesium oxide can carry, so the label's numbers agree with its salt.
computed| Measure | Value |
|---|---|
| Label text (NIH DSLD statements) | 400 mg Magnesium Oxide, equivalent to approximately 240 mg of elemental Magnesium |
| Implied magnesium share | 60.0% |
| Most magnesium oxide can carry | 60.3% |
Source · NIH DSLD 309690 label text · snapshot 2026-08-10; salt fractions from the chemistry model · release 2026-08-10-f441aa9f · CSV · method
How much elemental magnesium is actually in this label's filed magnesium lines?
Geri-Care Magnesium Oxide 400 mg files 1 magnesium line in NIH DSLD 309690; the selected primary line declares 480 mg of elemental magnesium per serving, against 0 other rows excluded from the primary amount. A salt named under another nutrient does not turn that nutrient's quantity into elemental magnesium.
measured| Filed amount | Salt or note as filed | Role |
|---|---|---|
| 480 mg | Salt not named in this row; magnesium oxide is taken from the label text | Primary serving |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Does this label's oxide claim hold up, or could the magnesium come from another source?
The label names one magnesium form, oxide, resolved from the full NIH DSLD record text; capsule capacities do not apply to this form, compared with oxide, the salt richest in magnesium at 60.3%.
computed with assumption| Form named on the label | Elemental fraction | Source |
|---|---|---|
| Magnesium oxide | 60.3% | full NIH DSLD record text |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Is this a good price for the elemental magnesium I'm actually getting?
No US retail price is matched to this label as of 2026-11-02; 10 of 61 oxide labels have one, against a median of $0.0293 per 100 mg among 5 ranked oxide offers.
computed
Chart data
| Displayed chart text |
|---|
| n=5 |
| P25 $0.0258 |
| P75 $0.0356 |
| median $0.0293 |
| Rank | Label | Per 100 mg | Observed |
|---|---|---|---|
| 1 | Nutricost Magnesium Oxide | $0.0148 | 2026-11-02 |
| 2 | tnvitamins Magnesium Oxide 420 mg | $0.0258 | 2026-11-02 |
| 3 | Douglas Laboratories Magnesium Oxide | $0.0293 | 2026-11-02 |
| 4 | Wonder Labs Magnesium Oxide 400 | $0.0356 | 2026-11-02 |
| 5 | Carlson Magnesium Gels 400 mg | $0.0636 | 2026-11-02 |
| Median | 5 ranked oxide offers | $0.0293 | 2026-11-02 |
Source · Amazon via licensed data provider; NIH DSLD · unique ASIN × date; prices observed 2026-10-26 to 2026-11-02 · release 2026-08-10-f441aa9f · CSV · method
How many days will this bottle last at the label's own serving, and what does a day cost?
At the label's own serving, Geri-Care Magnesium Oxide 400 mg lasts 60 days: 60 servings against 1 serving a day in the filed directions.
computed| Measure | Value |
|---|---|
| Net contents as filed | 120 Coated Tablet(s) |
| Serving size as filed | 1–2 Tablet(s) |
| Servings per container | 60 |
| Servings per day in the directions | 1 |
| Days per bottle | 60 days |
| $ per 30 days at one label serving a day | No ranked price as of 2026-11-02 |
| $ per 30 days at 420 mg Daily Value | No ranked price as of 2026-11-02 |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What does "114% Daily Value" mean here, and does it recompute?
The label declares 114% Daily Value; 480 mg against the 420 mg reference in 21 CFR 101.9 recomputes to 114%, the same within one point.
computed| Group as filed | Declared | Reference | Recomputed |
|---|---|---|---|
| Adults and children 4 or more years of age | 114% | 420 mg | 114% |
Source · NIH DSLD 309690; 21 CFR 101.9 · label 2024-06-20 · release 2026-08-10-f441aa9f · CSV · method
Why does this label contain magnesium stearate, what shell is it, and who is it filed for?
Geri-Care Magnesium Oxide 400 mg files 9 other ingredients, including magnesium stearate (reference fraction 4.1% magnesium; no quantity filed, so it is not added to the total) and a vegetarian shell, against 30 of 61 oxide labels that list magnesium stearate.
measured| Entry | Filed ingredient or declaration |
|---|---|
| 1 | Microcrystalline Cellulose |
| 2 | Croscarmellose Sodium |
| 3 | Stearic Acid |
| 4 | Magnesium Stearate |
| 5 | Hypromellose |
| 6 | Talc |
| 7 | Titanium Dioxide |
| 8 | Polyethylene Glycol |
3 additional rows
| Entry | Filed ingredient or declaration |
|---|---|
| 9 | Wax |
| Shell | vegetarian |
| Target group | Adult (18 - 50 Years) |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
What has research measured about oxide, and about side effects?
12 studies in the PubMed-checked registry measured outcomes involving oxide; 2 mention gastrointestinal or adverse outcomes. They measured the salt, not this label.
measured| Year | Study | PubMed |
|---|---|---|
| 2026 | Randomized, open-label study of the short-term pharmacokinetics of oral magnesium oxide in healthy volunteers. | 42091979 |
| 2024 | Comparative Clinical Study on Magnesium Absorption and Side Effects After Oral Intake of Microencapsulated Magnesium (MAGSHAPE™ Microcapsules) Versus Other Magnesium Sources. | 39770988 |
| 2022 | Effects of short-term magnesium supplementation on ionized, total magnesium and other relevant electrolytes levels. | 35041150 |
Source · PubMed-checked study registry · registry checked 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Has this brand had FDA recalls or adverse event reports?
Geri-Care has 0 FDA recall records matched by brand name in the enforcement data queried 2026-10-19. Geri-Care has FDA CAERS adverse event reports on record at brand level, as do 143 of 273 brands in this registry; openFDA states that “there is no certainty that the reported event (adverse event) was actually due to the product” and that reports “cannot be used to estimate the incidence of these events.”
measured| Recall | Date | Reason | Status |
|---|---|---|---|
| No recall record as of 2026-10-19 |
Source · openFDA enforcement and CAERS · queried 2026-10-19 · release 2026-08-10-f441aa9f · CSV · method
Is this the same formula as another brand's, and how do their prices differ?
No other brand files the same formulation (ingredients, shell, units and rounded amount) as of 2026-11-02.
computed| Label | Brand | Price per 100 mg |
|---|---|---|
| No cross-brand match as of 2026-11-02 |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Which labels are closest to this one, with the same salt and dose?
No other label files the same resolved salt within ±10% of this label's dose per unit as of 2026-11-02.
computed| Label | Elemental per unit | Price | Verdict |
|---|---|---|---|
| No neighbour as of 2026-11-02 |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
Where does this record come from, what is missing, and how do I cite or correct it?
Every value on this page traces to NIH DSLD 309690 (label 2024-06-20, snapshot 2026-08-10) and the chemistry model of 2026-09-13. 1 gap remain: No US retail price matched as of 2026-11-02 (barcode 3 57896 63412 4). The CSV carries the values shown here.
measured| Field | As filed |
|---|---|
| NIH DSLD label | NIH DSLD 309690 |
| Scanned label (PDF) | Label 309690 scan |
| Label date | 2024-06-20 |
| Date entered into DSLD | 2024-06-20 |
| Barcode (UPC) as filed | 3 57896 63412 4 |
| Label version · Image difference, same product | NIH DSLD 176733 |
| Label version · Image difference, same product | NIH DSLD 255316 |
| Distributed by | Geri-Care Pharmaceuticals Corp., Brooklyn, NY |
19 additional rows
| Field | As filed |
|---|---|
| Claim category as filed | Nutrient |
| Claim category as filed | All Other |
| Claim category as filed | Structure/Function |
| Formula re: Contains | Each tablet contains 400 mg Magnesium Oxide, equivalent to approximately 240 mg of elemental Magnesium. |
| Suggested/Recommended/Usage/Directions | Suggested Use: Adults-Take 1 to 2 tablets daily as a dietary supplement, or as directed by a doctor. |
| Precautions re: All Other | Do not exceed recommended dose. |
| Precautions re: Pregnant or Nursing or Prescription Medications | Warnings; Consult a physician before use if you are taking any prescription drug or if you have kidney disease. |
| Precautions re: All Other | May have a laxative effect. |
| Formula re: Contains | Elemental Magnesium 240 mg per tablet |
| General Statements: All Other Content | Compare to active ingredient in Mag-Ox 400 |
| FDA Statement of Identity | Dietary Supplement |
| Precautions re: Pregnant or Nursing or Prescription Medications | As with any supplement, if you are pregnant, nursing or taking medication, ask a health professional before use. |
| Precautions re: Children | Keep out of reach of children. |
| Precautions re: All Other | In case of overdose, get medical help or contact a Poison Control Center right away. Tamper Evident: Do not use if imprinted seal under cap is missing or broken. |
| Storage | Store at room temperature. |
| Brand IP Statement(s) re: (c), (TM), (SM) | This product is not manufactured or distributed by the owner of the registered trademark Mag-Ox 400. |
| Formulation re: Other | Product of India |
| Physical state | Tablet or Pill |
| Registry snapshot | 2026-08-10 |
Source · NIH DSLD 309690 · label 2024-06-20; snapshot 2026-08-10 · release 2026-08-10-f441aa9f · CSV · method
6 brand pages linked below contain magnesium labels from the NIH DSLD registry snapshot dated 2026-08-10.