When This Medicine Should Not Be Used:
You should not receive this medicine if you have had an allergic reaction to antivenin, or if you have any history of allergy to horses or any products that come from horses. You should not receive morphine or other narcotic pain medicines if you are receiving this medicine.

How to Use This Medicine:
Injectable

• Your doctor will prescribe your dose and schedule. This medicine is given through a needle placed in a vein.
• A nurse or other health provider will give you this medicine. This medicine is given slowly, so the needle may remain in place for an hour or longer.
• Your care providers will need to watch you closely during your treatment. This is to make sure the medicine is working and does not cause serious side effects.

Drugs and Foods to Avoid:
Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Make sure your doctor knows if you are using beta blockers (such as atenolol, metoprolol, propranolol, or Toprol®) and other blood pressure medicines.
• Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.

Warnings While Using This Medicine:

• Make sure your doctor knows if you are pregnant or breastfeeding, or if you have asthma, hay fever, or hives.
• Your doctor will need to perform a skin test to see if you are at risk of having a serious reaction to this medicine.

Possible Side Effects While Using This Medicine:
Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Fever.
• Headache, stiff neck, vision changes.
• Lightheadedness or fainting.
• Numbness, tingling, or burning pain in your shoulders, hands, arms, legs, or feet.
• Pain, itching, burning, swelling, or a lump under your skin where the needle is placed.
• Shortness of breath, bluish-colored skin, or cough.
• Swelling in your hands, ankles, or feet.
• Warmth or redness in your face, neck, arms, or upper chest.

If you notice these less serious side effects, talk with your doctor:

• Enlarged lymph nodes, or lumps on your neck, armpit, or groin.
• Joint pain.
• Muscle pain or weakness.
• Nausea or vomiting.

If you notice other side effects that you think are caused by this medicine, tell your doctor.
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088