alosetron vs rolapitant

PlainMeds reviewed this comparison against our methodology in August 2026. It places FDA and CMS record fields side by side, without recommending either medication.

Side-by-side comparison of alosetron and rolapitant. 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)
rolapitant NK1 Receptor Antagonist (Antiemetic)
Type
alosetron Prescription
rolapitant Prescription
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.

rolapitant

Varubi is a medicine that helps prevent nausea and vomiting caused by chemotherapy. It is used with other anti-nausea medicines.

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.

rolapitant

Varubi is used to prevent delayed nausea and vomiting in adults. This nausea and vomiting is caused by cancer chemotherapy. It is used for both the first and repeat treatments of chemotherapy.

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.

rolapitant

Varubi blocks a substance in your body called substance P/neurokinin 1 (NK1). This substance can cause nausea and vomiting. By blocking it, Varubi helps prevent these side effects from chemotherapy.

Common Side Effects
alosetron
  • Constipation
  • Abdominal discomfort and pain
  • Nausea
  • Gastrointestinal discomfort and pain
rolapitant
  • Neutropenia (low white blood cell count)
  • Hiccups
  • Abdominal pain
  • Decreased appetite
  • Dizziness
FAERS Reports
alosetron
  • Diarrhoea 10
  • Nausea 8
  • Abdominal Pain 6
  • Death 6
  • Constipation 5
rolapitant
  • Death 141
  • Nausea 79
  • Fatigue 50
  • Infusion Related Reaction 40
  • Dyspnoea 34
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.

rolapitant

You should not take Varubi if you are taking thioridazine or pimozide. These drugs can cause serious heart problems if taken with Varubi. Varubi can increase the levels of these drugs in your blood, leading to QT prolongation and Torsades de Pointes, which are dangerous heart rhythm problems.

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.

rolapitant

There is not enough information about Varubi use in pregnant women to know if it is safe. Talk to your doctor if you are pregnant or plan to become pregnant. It is not known if Varubi passes into breast milk. Talk to your doctor if you are breastfeeding.

Also Compare, Nearby Drugs

Compare rolapitant with

How to Read This alosetron vs rolapitant Comparison

alosetron is classified in the 5-HT3 Antagonist (IBS-D) drug class, while rolapitant sits within the NK1 Receptor Antagonist (Antiemetic) class. Drugs from different classes work through distinct mechanisms, so a head-to-head comparison illustrates trade-offs rather than equivalence. Both drugs are prescription-only, so a licensed provider must authorize use.

Adverse event totals above are pulled from the FDA's Adverse Event Reporting System (FAERS). For these top-ranked reactions alone, alosetron has 35 submissions while rolapitant has 344. 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 represent individual circumstances. Data here is sourced from FDA Structured Product Labels (SPL) and FAERS, both of which update as manufacturers and clinicians submit new information. This registry does not provide medical, treatment, substitution, or medication-change directions for alosetron or rolapitant.

Registry boundary: This comparison displays source-record fields and does not provide individualized medical direction.