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Two medicines, side by side

Bisacodyl vs lactulose

Bisacodyl and lactulose are both labeled for constipation. Pharmacies paid $0.320 per bisacodyl 10 mg suppository and $8.22 per packet (Lactulose 10 g packet) (NADAC, October 7, 2026); the strengths differ, so the two prices are not like for like.

Check it at the source: the bisacodyl FDA label on DailyMed (effective April 8, 2025); the lactulose FDA label on DailyMed (effective January 28, 2026).

Highlights of the bisacodyl record

Bisacodyl · label of April 8, 2025

Used for

From the label: indications

● for relief of occasional constipation and irregularity ● this product generally produces bowel movement in 6 to 12 hours Use ● for relief of occasional constipation and irregularity ● this product generally produces bowel movement in 6 to 12 hours

On the market

Earliest approval on file
n/a
Generic labelers
none listed
Pharmacy cost
$0.320 per suppository

Supply and safety

Shortage
No current entry
Recalls
0

Highlights of the lactulose record

Lactulose (Enulose) · label of January 28, 2026

Used for

From the label: indications

For the treatment of constipation. In patients with a history of chronic constipation, lactulose solution therapy increases the number of bowel movements per day and the number of days on which bowel movements occur.

On the market

Earliest approval on file
March 25, 1976
Generic labelers
22 labelers
Pharmacy cost
$8.22 per packet

Supply and safety

Shortage
No current entry
Recalls
7

Source: FDA drug labels via openFDA (Bisacodyl label of April 8, 2025, Lactulose label of January 28, 2026); NDC Directory, Drugs@FDA, NADAC, FDA shortages and recalls (October 8, 2026)

How do bisacodyl and lactulose differ on the record?

Generics: bisacodyl none approved; lactulose since 1988 (Drugs@FDA).

BisacodylLactulose
Labeled forConstipationConstipation
Pharmacologic classn/aOsmotic Laxative
How it works (label)n/an/a
Half-life (label)n/an/a
Earliest approval on file (Drugs@FDA)n/aMarch 25, 1976
First generic approvednoneJuly 26, 1988
Generic labelers (NDC)none listed22 labelers
Pharmacy cost (NADAC, each one's most listed form; strengths differ)$0.320 per suppository (Bisacodyl 10 mg suppository)$8.22 per packet (Lactulose 10 g packet)
12-month price change-4%+10%
Boxed warningNoNo
Shortage nowNo current entryNo current entry
Recalls recorded07
FAERS reports (a report is not proof of cause; counts follow how widely a medicine is used)14,16138,214
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 bisacodyl
every medicine labeled for the same conditions