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Two medicines, side by side

Magnesium citrate vs magnesium hydroxide

Magnesium citrate and magnesium hydroxide are both labeled for constipation. Pharmacies paid $0.0066 per mL (Magnesium citrate solution) and $0.0095 per mL (Milk of magnesia suspension) (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like.

Check it at the source: the magnesium citrate FDA label on DailyMed (effective September 1, 2026); the magnesium hydroxide FDA label on DailyMed (effective August 21, 2026).

Highlights of the magnesium citrate record

Magnesium citrate · label of September 1, 2026

Used for

From the label: indications

relieves occasional constipation (irregularity) generally produces bowel movement in 1/2 to 6 hours

On the market

Earliest approval on file
n/a
Generic labelers
none listed
Pharmacy cost
$0.0066 per mL

Supply and safety

Shortage
No current entry
Recalls
1

Highlights of the magnesium hydroxide record

Magnesium hydroxide · label of August 21, 2026

Used for

From the label: indications

relieves 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

Source: FDA drug labels via openFDA (Magnesium citrate label of September 1, 2026, Magnesium hydroxide label of August 21, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)

How do magnesium citrate and magnesium hydroxide differ on the record?

Magnesium citrateMagnesium hydroxide
Labeled forConstipationConstipation, Acid reflux and ulcers
Pharmacologic classn/an/a
How it works (label)n/an/a
Half-life (label)n/an/a
Earliest approval on file (Drugs@FDA)n/an/a
First generic approvednonenone
Generic labelers (NDC)none listednone listed
Pharmacy cost (NADAC, each one's most listed form; strengths differ)$0.0066 per mL (Magnesium citrate solution)$0.0095 per mL (Milk of magnesia suspension)
12-month price change+6%-2%
Boxed warningNoNo
Shortage nowNo current entryNo current entry
Recalls recorded16
FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used)6,10413,458
DEA schedulenonenone

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 citrate
every medicine labeled for the same conditions