Alternatives to Bisac-Evac If You Can't Fill Your Prescription

Can't Find Bisac-Evac? You Have Other Options

If your pharmacy is out of Bisac-Evac and you're dealing with constipation, don't panic. There are several effective alternatives that can help you get relief. Some work the same way as Bisac-Evac, while others take a different approach to treating constipation.

In this guide, we'll explain what Bisac-Evac is, how it works, and walk you through the best alternatives available in 2026.

What Is Bisac-Evac?

Bisac-Evac is a brand name for Bisacodyl, a stimulant laxative. It's one of the most commonly used over-the-counter treatments for occasional constipation. You may also know it by other brand names like Dulcolax, Correctol, and Alophen.

Bisac-Evac comes in three forms:

• Enteric-coated oral tablets (5 mg)
• Rectal suppositories (10 mg)
• Rectal enemas (10 mg)

For a deeper look at this medication, check out our article on what Bisac-Evac is and how to use it.

How Does Bisac-Evac Work?

Bisac-Evac belongs to the stimulant laxative class. It works in two ways:

1. Stimulates intestinal contractions: Bisacodyl activates nerve endings in the intestinal wall, triggering rhythmic muscle movements (peristalsis) that push stool through the colon.
2. Increases water in the colon: It also promotes the accumulation of water and electrolytes in the intestines, which softens stool and makes it easier to pass.

Oral tablets typically produce a bowel movement in 6 to 12 hours, while suppositories work in 15 to 60 minutes. For more details, read how Bisac-Evac works.

The Best Alternatives to Bisac-Evac

If you can't find Bisac-Evac, here are four effective alternatives. We've organized them from the most similar option to the gentlest.

1. Senna (Senokot, Ex-Lax)

Type: Stimulant laxative
How it works: Like Bisac-Evac, Senna is a stimulant laxative. It contains compounds called sennosides that stimulate the muscles of the intestine to contract, moving stool through the colon. It's a plant-based laxative derived from the senna plant.
How fast it works: Oral Senna typically works in 6 to 12 hours — similar timing to Bisac-Evac tablets.
Availability: Widely available over the counter as Senokot, Ex-Lax, and store-brand generics.
Cost: About $5 to $12 for a 30-100 count bottle.
Best for: People who want a stimulant laxative similar to Bisac-Evac. This is the closest direct substitute.

2. Polyethylene Glycol (MiraLAX)

Type: Osmotic laxative
How it works: MiraLAX works differently from Bisac-Evac. Instead of stimulating intestinal muscles, it draws water into the colon through osmosis. This softens the stool and increases its volume, which naturally triggers a bowel movement.
How fast it works: Typically 1 to 3 days for full effect — slower than Bisac-Evac but gentler on the system.
Availability: Extremely widely available over the counter at virtually every pharmacy and retailer.
Cost: About $10 to $25 for a 14-30 day supply.
Best for: People who need ongoing constipation relief and prefer a gentler approach. MiraLAX is often recommended as a first-line OTC treatment for chronic constipation.

3. Magnesium Hydroxide (Milk of Magnesia)

Type: Osmotic / saline laxative
How it works: Milk of Magnesia draws water into the intestines and can also mildly stimulate intestinal contractions. It's been used for constipation relief for over a century.
How fast it works: Usually 30 minutes to 6 hours — faster than MiraLAX and comparable to Bisac-Evac in many cases.
Availability: Widely available over the counter.
Cost: About $4 to $10 for a 12 oz bottle.
Best for: People who want relatively quick relief without the cramping that stimulant laxatives can sometimes cause.

4. Docusate Sodium (Colace)

Type: Stool softener
How it works: Colace doesn't stimulate your intestines at all. Instead, it softens stool by allowing water and fats to penetrate it, making it easier to pass. It's the gentlest option on this list.
How fast it works: Usually 12 to 72 hours — the slowest option, but with the fewest side effects.
Availability: Widely available over the counter.
Cost: About $5 to $12 for a 30-60 count bottle.
Best for: People with mild constipation or those who need to avoid straining (such as after surgery or with hemorrhoids).

Quick Comparison Chart

Here's a summary to help you decide:

• Senna — Stimulant laxative, works in 6-12 hours, $5-$12, closest to Bisac-Evac
• MiraLAX — Osmotic laxative, works in 1-3 days, $10-$25, gentlest for chronic use
• Milk of Magnesia — Saline laxative, works in 30 min-6 hours, $4-$10, fast and affordable
• Colace — Stool softener, works in 12-72 hours, $5-$12, best for mild cases

Important Things to Keep in Mind

Before switching to an alternative, consider these tips:

• Talk to your doctor or pharmacist before switching, especially if you take other medications. Some laxatives can interact with certain drugs. Check out our guide on Bisac-Evac drug interactions for more info.
• Don't use stimulant laxatives for more than 7 days without medical advice. Long-term use can cause your bowels to become dependent on them.
• Stay hydrated. All laxatives work better when you drink plenty of water.
• Consider lifestyle changes. Increasing fiber intake, exercise, and water consumption can help reduce your need for laxatives over time.

Still Looking for Bisac-Evac?

If you'd rather stick with Bisac-Evac specifically, use Medfinder to check which pharmacies near you have it in stock. You can also read our guide on how to find Bisac-Evac in stock near you for more tips.

Final Thoughts

Not being able to find your usual medication is frustrating, but constipation doesn't have to wait. Whether you choose Senna as a close substitute, MiraLAX for a gentler approach, or Milk of Magnesia for fast relief, there are plenty of effective alternatives to Bisac-Evac available at most pharmacies.

The most important thing is to find something that works for you — and to talk with your doctor if constipation is an ongoing issue. You shouldn't have to suffer just because one brand is hard to find.