Maropitant

What is this medication for?

• Prevention/treatment of acute vomiting (under the skin); prevention of acute vomiting and motion sickness (by mouth)
• Vomiting (various causes), including CKD-associated nausea

How is it given?

Give exactly as your veterinarian prescribed — never change the dose or stop on your own unless your veterinarian has told you to.

• Refrigerate the injectable vial before drawing up a dose — this measurably reduces injection pain, a well-documented practical tip.
• Revised labeling now supports use up to 14 consecutive days at higher doses, or indefinitely in dogs >7 months until the underlying condition resolves — don't assume the older 5-day/2-day-washout rule still applies.
• Always look for and treat the underlying cause of protracted vomiting rather than relying on maropitant alone to mask ongoing disease.

What if I miss a dose?

• Give it as soon as you remember — unless it is almost time for the next dose (then skip the missed one; never double up).
• Call your clinic if you miss more than one dose in a row.

Side effects — what should I watch for?

Effects listed as common in this handout

• Hypersalivation, pre-travel vomiting (motion-sickness dosing) (Most common with oral high-dose tablets)
• Diarrhea (4–8%), loss of appetite (1.5–5.2%) (US field trial data)

Worth a phone call to your veterinarian

• Pain/swelling at under the skin injection site (Common, reduced by refrigerating vial before use)

⚠️ Contact your veterinarian or an emergency clinic IMMEDIATELY if you notice

• Trouble breathing, collapse, seizures, severe vomiting or diarrhea, facial swelling, or pale gums

Before starting (or refilling), tell your veterinarian if your pet:

• has or has had: None absolute
• has or has had: Hepatic dysfunction (hepatically metabolized); puppies <11 weeks (bone marrow hypoplasia signal in studies)

• is pregnant, nursing, or used for breeding
• is taking any other medications, supplements, or flea/tick products, including:
  • None specifically identified
  • Alkalinizing into a vein solutions

Storage and handling

Room temperature (label) but refrigeration before injection reduces injection-site pain (cyclodextrin complex more stable cold). Discard vial 28 days after first puncture.

Good to know

• Refrigerate the injectable vial before drawing up a dose — this measurably reduces injection pain, a well-documented practical tip.
• Revised labeling now supports use up to 14 consecutive days at higher doses, or indefinitely in dogs >7 months until the underlying condition resolves — don't assume the older 5-day/2-day-washout rule still applies.
• Always look for and treat the underlying cause of protracted vomiting rather than relying on maropitant alone to mask ongoing disease.