Two medicines, side by side
Magnesium hydroxide vs magnesium oxide
Magnesium hydroxide and magnesium oxide are both labeled for acid reflux and ulcers. Pharmacies paid $0.0095 per mL (Milk of magnesia suspension) and $0.0346 per magnesium oxide 400 mg tablet (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like.
Check it at the source: the magnesium hydroxide FDA label on DailyMed (effective August 21, 2026); the magnesium oxide FDA label on DailyMed (effective July 6, 2026).
Highlights of the magnesium hydroxide record
Magnesium hydroxide · label of August 21, 2026
Used for
From the label: indicationsrelieves occasional constipation (irregularity). This product usually produces bowel movement in 1/2 to 6 hours.
On the market
- Earliest approval on file
- n/a
- Generic labelers
- none listed
- Pharmacy cost
- $0.0095 per mL
Supply and safety
- Shortage
- No current entry
- Recalls
- 6
Highlights of the magnesium oxide record
Magnesium oxide · label of July 6, 2026
Used for
From the label: indicationsrelieves: acid indigestion upset stomach
On the market
- Earliest approval on file
- n/a
- Generic labelers
- none listed
- Pharmacy cost
- $0.0346 per tablet
Supply and safety
- Shortage
- No current entry
- Recalls
- 0
Source: FDA drug labels via openFDA (Magnesium hydroxide label of August 21, 2026, Magnesium oxide label of July 6, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)
How do magnesium hydroxide and magnesium oxide differ on the record?
| Magnesium hydroxide | Magnesium oxide | |
|---|---|---|
| Labeled for | Constipation, Acid reflux and ulcers | Acid reflux and ulcers |
| Pharmacologic class | n/a | n/a |
| How it works (label) | n/a | n/a |
| Half-life (label) | n/a | n/a |
| Earliest approval on file (Drugs@FDA) | n/a | n/a |
| First generic approved | none | none |
| Generic labelers (NDC) | none listed | none listed |
| Pharmacy cost (NADAC, each one's most listed form; strengths differ) | $0.0095 per mL (Milk of magnesia suspension) | $0.0346 per tablet (Magnesium oxide 400 mg tablet) |
| 12-month price change | -2% | -4% |
| Boxed warning | No | No |
| Shortage now | No current entry | No current entry |
| Recalls recorded | 6 | 0 |
| FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used) | 13,458 | 42,078 |
| DEA schedule | none | none |
Source: Drugs@FDA, FDA NDC Directory, CMS NADAC of October 7, 2026, FDA shortages and recalls, FAERS via openFDA (FDA files October 8, 2026)
What next?
- Alternatives to magnesium hydroxide
- every medicine labeled for the same conditions