When You Can't Get Amitiza, What Are Your Options?

If you rely on Amitiza (Lubiprostone) for chronic constipation and suddenly can't fill your prescription — whether because of a supply issue, cost, or insurance problems — you need to know what other options are out there. The good news is that several effective alternatives exist.

In this guide, we'll cover what Amitiza is, how it works, and the best prescription alternatives your doctor can consider if Amitiza isn't available. Important: Never switch medications on your own. Always talk to your doctor before starting or stopping any prescription drug.

What Is Amitiza and What Does It Treat?

Amitiza is the brand name for Lubiprostone, a chloride channel activator approved by the FDA for three conditions:

• Chronic idiopathic constipation (CIC) — ongoing constipation not caused by another medical condition or medication
• Irritable bowel syndrome with constipation (IBS-C) — approved specifically for women aged 18 and older
• Opioid-induced constipation (OIC) — constipation caused by opioid pain medications in people with chronic non-cancer pain

Amitiza comes as soft gelatin capsules in 8 mcg and 24 mcg strengths and is taken twice daily with food and water. For a complete overview, see: What Is Amitiza? Uses, Dosage, and What You Need to Know.

How Does Amitiza Work?

Amitiza works by activating ClC-2 chloride channels on the surface of cells lining your intestines. When these channels open, chloride ions and water flow into the intestinal lumen. This extra fluid softens stool and helps it move through the digestive tract more easily.

Unlike stimulant laxatives that force muscle contractions, Amitiza works by increasing natural fluid secretion. This makes bowel movements softer and more comfortable. For a deeper explanation, visit: How Does Amitiza Work? Mechanism of Action Explained.

Best Alternatives to Amitiza

The following prescription medications treat similar conditions to Amitiza. Each one works differently, so the best choice depends on your specific diagnosis, medical history, and what your insurance covers.

1. Linzess (Linaclotide)

Linzess is one of the most commonly prescribed alternatives to Amitiza. It's a guanylate cyclase-C (GC-C) agonist that increases fluid secretion in your intestines and can also help reduce abdominal pain.

• FDA-approved for: CIC and IBS-C
• Dosing: Once daily on an empty stomach, at least 30 minutes before your first meal
• Strengths: 72 mcg, 145 mcg, and 290 mcg capsules
• Key advantage: Once-daily dosing (compared to Amitiza's twice daily) and proven pain relief in IBS-C
• Common side effects: Diarrhea (most common), abdominal pain, flatulence

Linzess is widely available and may be easier to find than Amitiza at many pharmacies.

2. Trulance (Plecanatide)

Trulance is another GC-C agonist, similar to Linzess but designed to mimic the body's natural digestive hormone uroguanylin.

• FDA-approved for: CIC and IBS-C
• Dosing: 3 mg once daily, with or without food
• Key advantage: Can be taken with or without food, and some patients report fewer side effects compared to Linzess
• Common side effects: Diarrhea, abdominal distension

3. Motegrity (Prucalopride)

Motegrity works through a completely different mechanism than Amitiza. It's a selective serotonin 5-HT4 receptor agonist that stimulates the natural contractions of the colon.

• FDA-approved for: CIC in adults
• Dosing: 2 mg once daily (1 mg for patients with severe kidney impairment)
• Key advantage: Different mechanism of action — may work when secretagogues like Amitiza haven't been effective
• Common side effects: Headache, abdominal pain, nausea, diarrhea
• Note: Not approved for IBS-C or OIC

4. Movantik (Naloxegol) — For Opioid-Induced Constipation

If you take Amitiza specifically for opioid-induced constipation, Movantik is a targeted alternative. It's a peripherally acting mu-opioid receptor antagonist (PAMORA) that blocks opioid effects in the gut without affecting pain relief.

• FDA-approved for: OIC in adults with chronic non-cancer pain
• Dosing: 25 mg once daily on an empty stomach, at least 1 hour before or 2 hours after food
• Key advantage: Specifically designed for opioid-induced constipation without reducing pain control
• Common side effects: Abdominal pain, diarrhea, nausea, flatulence, headache

Other PAMORAs include Symproic (Naldemedine) and Relistor (Methylnaltrexone).

What About Over-the-Counter Options?

While prescription alternatives are the closest substitutes for Amitiza, some patients find relief with over-the-counter (OTC) options as a bridge while they search for their prescription:

• Polyethylene glycol (MiraLAX): An osmotic laxative that draws water into the colon
• Docusate sodium (Colace): A stool softener
• Fiber supplements (Metamucil, Benefiber): Bulk-forming laxatives

These OTC options may not be as effective as Amitiza for your condition, but they can help manage symptoms temporarily. Always check with your doctor first.

How to Decide Which Alternative Is Right for You

When discussing alternatives with your doctor, consider:

• Your diagnosis: CIC, IBS-C, and OIC have different approved treatments
• Dosing convenience: Most alternatives are once daily vs. Amitiza's twice daily
• Side effect profile: Nausea is more common with Amitiza; diarrhea is more common with Linzess and Trulance
• Cost and insurance: Check what your plan covers — some alternatives may have lower copays
• Previous medications: What you've tried before and how you responded

To find a doctor who can help you evaluate these options, see: How to Find a Doctor Who Can Prescribe Amitiza Near You.

Final Thoughts

If you can't fill your Amitiza prescription, you have real options. Linzess, Trulance, Motegrity, and Movantik are all effective prescription alternatives depending on your specific condition. Don't suffer through constipation without treatment — talk to your doctor about switching, and use Medfinder to check availability for whatever medication you decide on.