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alosetron vs senna

Side-by-side comparison of alosetron and senna Data from FDA drug databases (Orange Book, NDC Directory, recalls, shortages) covering 20,000+ approved drugs, plus CMS pricing; see our methodology.

Drug Class
alosetron 5-HT3 Antagonist (IBS-D)
senna Stimulant Laxative
Type
alosetron Prescription
senna Over-the-Counter
Summary
alosetron

Alosetron (Lotronex) is a medicine for women with severe diarrhea-predominant irritable bowel syndrome (IBS). It helps to reduce diarrhea and stomach pain.

senna

Senna (Senokot) is a stimulant laxative. It helps relieve constipation and usually causes a bowel movement in 6 to 12 hours.

What It Treats
alosetron

Alosetron is used to treat severe diarrhea-predominant irritable bowel syndrome (IBS) in women. It is for women whose IBS symptoms have lasted for 6 months or longer. You should have already ruled out other possible causes of your symptoms. This medicine is only for you if other treatments have not worked well enough.

senna

Senna treats occasional constipation, which means you have trouble having bowel movements. It helps your bowels move if you are irregular. This medicine usually works within 6 to 12 hours.

How It Works
alosetron

Alosetron blocks a substance called serotonin in your gut. Serotonin can speed up bowel movements. By blocking serotonin, alosetron slows down your bowel and reduces diarrhea.

senna

Senna is a stimulant laxative. It works by stimulating the muscles in your intestines. This helps to move stool through your body.

Common Side Effects
alosetron
  • Constipation
  • Abdominal discomfort and pain
  • Nausea
  • Gastrointestinal discomfort and pain
senna
  • Diarrhea
  • Abdominal pain
FAERS Reports
alosetron
  • Medicine not working 11
  • Diarrhea 10
  • Feeling sick to your stomach 8
  • Using the medicine for something it's not approved for 7
  • Stomach pain 6
senna
  • Feeling sick to your stomach 1,390
  • Feeling very tired 1,358
  • Having trouble having bowel movements 1,158
  • Difficulty breathing 1,093
  • Loose, watery stools 1,064
Serious Warnings
alosetron

Alosetron can cause serious gut problems, like ischemic colitis (reduced blood flow to the bowel) and severe constipation. These problems can lead to hospitalization, surgery, or even death. Stop taking alosetron right away if you get constipated or have symptoms of ischemic colitis, like bloody diarrhea or bad stomach pain. Call your doctor immediately.

senna

There are no boxed warnings in the provided data.

Pregnancy
alosetron

It is not known if alosetron can harm your unborn baby. Talk to your doctor if you are pregnant or plan to become pregnant. It is also not known if alosetron passes into breast milk. Talk to your doctor about the best way to feed your baby if you take alosetron.

senna

It is always best to talk to your doctor before taking any medication during pregnancy or breastfeeding. They can help you weigh the risks and benefits.

Also Compare — Nearby Drugs

Compare senna with

How to Read This alosetron vs senna Comparison

alosetron is classified in the 5-HT3 Antagonist (IBS-D) drug class, while senna sits within the Stimulant Laxative class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are split between OTC and prescription status, which affects access and supervision.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, alosetron has 42 submissions while senna has 6,063. Those figures reflect cumulative reporting volume — not per-patient risk — so older, widely dispensed drugs typically look worse on count alone. No direct interaction between these two drugs is listed in our FDA-derived dataset, though co-prescription still warrants pharmacist review. Serious warnings, pregnancy guidance, and contraindications can differ even when indications overlap.

A table cannot substitute for clinical judgment. Effectiveness, tolerability, drug-drug interactions with your other medications, kidney and liver function, pregnancy status, insurance formulary, and price all feed into a decision that only a licensed prescriber can make responsibly. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This page is for educational purposes only, is not medical advice, and should not be used to self-switch between alosetron and senna — always consult your physician or pharmacist first.

Important: This comparison is for informational purposes only. Drug effects vary between individuals. Always consult your doctor or pharmacist for personalized medical advice.