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Generic name: obiltoxaximab

What is Anthim?

  • Anthim is a prescription medicine used along with antibiotic medicines to treat people with inhalational anthrax. Anthim can also be used to prevent anthrax disease when there are no other treatment options.
  • The effectiveness of Anthim has been studied only in animals with inhalational anthrax. There have been no studies in people who have inhalational anthrax.
  • The safety of Anthim was studied in healthy adults. There have been no studies of Anthim in children younger than 18 years.
  • Anthim is not used in prevention or treatment of anthrax meningitis.

What is the most important information I should know about Anthim?

Anthim can cause serious side effects, including:

  • Serious allergic reactions. Tell your healthcare provider right away if you have itching, hives, rash, throat irritation, cough, dizziness, shortness of breath or chest discomfort while receiving Anthim.

What should I tell my healthcare provider before using Anthim?

Before you receive Anthim, tell your healthcare provider about all of your medical conditions, including if you are:

  • allergic to obiltoxaximab or any of the ingredients in Anthim. See the end of this guide for a list of ingredients in Anthim.
  • allergic to diphenhydramine (Benadryl)
  • pregnant or planning to become pregnant. It is not known if Anthim will harm your unborn baby.
  • breastfeeding or plan to breastfeed. It is not known if Anthim passes into your breast milk. You and your healthcare provider should decide if you will receive Anthim or breastfeed.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements.

How should I use Anthim?

  • You will be given 1 dose of Anthim by a healthcare provider through a vein (IV or intravenous infusion). It takes about 1 hour and 30 minutes to give you the full dose of medicine.
  • Your healthcare provider should give you a medicine called diphenhydramine (Benadryl) before you receive Anthim to help reduce your chances of developing a skin reaction from Anthim. Benadryl may be given to you to take by mouth or through a vein.
  • Benadryl may make you sleepy, and you should use caution if you will be driving or operating equipment.

What are the possible side effects of Anthim?

The most common side effects of Anthim include headache, itching, upper respiratory tract infections, cough, IV site bruising, swelling and/or pain, stuffy nose (nasal congestion), hives, and pain in the hands or feet.

Tell your healthcare provider if you have any side effect that bothers you or that does not go away. These are not all the possible side effects of Anthim. For more information, ask your healthcare provider.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

General information about the safe and effective use of Anthim

This patient information leaflet summarizes the most important information about Anthim. If you would like more information, talk to your healthcare provider. You can ask your pharmacist or healthcare provider for information about Anthim that is written for health professionals.

How should I store Anthim?

  • Store in refrigerator at 2°C to 8°C (36°F to 46°F) in original carton to protect from light.
  • Do Not Freeze.
  • Do Not Shake.

What are the ingredients in Anthim?

Active ingredient: Obiltoxaximab

Inactive ingredients: L-histidine, sorbitol and polysorbate 80

For more information call 1-844-808-0222.

Source: National Library of Medicine. Last updated November 29, 2019.