Antivenin (Crotalidae) (By injection)

There may be other brand names for this medicine.

You should not use this medicine if you have had an allergic reaction to papaya or to products that contain an enzyme called papain.

Your doctor will prescribe your exact dose and tell you how often it should be given. This medicine is given through a needle placed in one of your veins.
This medicine works best when it is given within 6 hours after you were bitten by a rattlesnake.
A nurse or other trained health professional will give you this medicine. The medicine is given slowly, so the needle will remain in place for an hour or longer.
Your care providers will need to watch you for at least one hour after your injection. This is to make sure the medicine is working and does not cause serious side effects.

Make sure your doctor knows if you are pregnant or breastfeeding, or if you have cancer, connective tissue disorders, congestive heart failure, diarrhea, fever, liver disease, malnourishment, or overactive thyroid.
Tell your doctor if you have ever had an allergy to chymopapain, pineapple, dust mites, or latex rubber.

Allergic reaction: Itching or hives, swelling in face or hands, swelling or tingling in the mouth or throat, tightness in chest, trouble breathing
Black, tarry stools
Lightheadedness or fainting
Fast heartbeat
Fever, low back pain, wheezing, or nausea while you are receiving the injection
Fever, skin rash, muscle pain, and joint pain that occur in the weeks after you receive the medicine
Unusual bleeding or bruising that occurs in the weeks after you receive the medicine
Wheezing or cough

Last Updated: 1/27/2017