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Two medicines, side by side

Polyethylene glycol 3350 vs magnesium hydroxide

Polyethylene glycol 3350 and magnesium hydroxide are both labeled for constipation. Pharmacies paid $0.0286 per gram (Polyethylene glycol 3350 powd) 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 polyethylene glycol 3350 FDA label on DailyMed (effective May 4, 2026); the magnesium hydroxide FDA label on DailyMed (effective August 21, 2026).

Highlights of the polyethylene glycol 3350 record

Polyethylene glycol 3350 (Miralax) · label of May 4, 2026

Used for

From the label: indications

relieves occasional constipation (irregularity) generally produces a bowel movement in 1 to 3 days

On the market

Earliest approval on file
February 18, 1999
Generic labelers
69 labelers
Pharmacy cost
$0.0286 per gram

Supply and safety

Shortage
No current entry
Recalls
4

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 (Polyethylene glycol 3350 label of May 4, 2026, Magnesium hydroxide label of August 21, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)

How do polyethylene glycol 3350 and magnesium hydroxide differ on the record?

Generics: polyethylene glycol 3350 since 2004; magnesium hydroxide none approved (Drugs@FDA).

Polyethylene glycol 3350Magnesium hydroxide
Labeled forConstipationConstipation, Acid reflux and ulcers
Pharmacologic classOsmotic Laxativen/a
How it works (label)n/an/a
Half-life (label)n/an/a
Earliest approval on file (Drugs@FDA)February 18, 1999n/a
First generic approvedJuly 2, 2004none
Generic labelers (NDC)69 labelersnone listed
Pharmacy cost (NADAC, each one's most listed form; strengths differ)$0.0286 per gram (Polyethylene glycol 3350 powd)$0.0095 per mL (Milk of magnesia suspension)
12-month price change-1%-2%
Boxed warningNoNo
Shortage nowNo current entryNo current entry
Recalls recorded46
FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used)105,25413,458
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 polyethylene glycol 3350
every medicine labeled for the same conditions