Type of medicine: black widow spider antivenin
Generic and brand names: antivenin (latrodectus mactans), injection;
This medicine is given by injection (shots) to treat symptoms from black widow spider bites.
This medicine is made from horse serum. Some people are very allergic to medicines made from horse serum. Tell your healthcare provider if you have ever had:
It is also helpful to tell the provider:
Females of childbearing age: Talk with your healthcare provider if you are pregnant or plan to become pregnant. It is not known whether this medicine will harm an unborn baby. Do not breast-feed while taking this medicine without your healthcare provider's approval.
This medicine works best when injected within a few hours after the bite. However, this medicine may be given as long as 90 hours after the bite. The injections are usually given in a hospital or clinic.
Your healthcare provider may test you to see if you are allergic to this medicine before you receive it. This test may be given as a shot, just below the skin, of a small amount of diluted medicine. If you get a hive (raised areas on the skin with or without redness or rash) within 5 to 30 minutes, you have a positive reaction. This allergy test may also be given in the form of an eye drop. If your eyes itch or become red, you have a positive reaction. The sooner a positive reaction occurs, the more sensitive you are to this medicine. Even if you have a negative reaction, you may develop an allergic reaction in the future.
After you receive this medicine your healthcare provider will carefully watch you for any serious side effects. Follow your healthcare provider's advice.
Serum sickness, which is a delayed reaction to this medicine, may occur. Alert your healthcare provider if you have extreme tiredness, hives or rash, fever, swollen lymph glands, sore muscles or joints, or nausea and vomiting.
If you need emergency care, surgery, or dental work, tell the healthcare provider or dentist you have received this medicine.
Along with its needed effects, your medicine may cause some unwanted side effects. Some side effects may be very serious. Some side effects may go away as your body adjusts to the medicine. Tell your healthcare provider if you have any side effects that continue or get worse.
Life threatening (Report these to your healthcare provider right away. If you cannot reach your healthcare provider right away, get emergency medical care or call 911 for help.): Allergic reaction (hives, itching, rash, tightness in your chest, trouble breathing, swelling of the tongue and throat).
Serious (report these to your healthcare provider right away): Serum sickness (fever, rash, unusual tiredness or weakness, joint or muscle pain, nausea, vomiting, swollen lymph glands) 5 to 21 days after treatment.
Other: Muscle cramps, irritation at the injection site.
No significant interactions have been reported.
If you are not sure if your medicines might interact, ask your pharmacist or healthcare provider. Keep a list of all your medicines with you. List all the prescription medicines, nonprescription medicines, supplements, natural remedies, and vitamins that you take. Be sure that you tell all healthcare providers who treat you about all the products you are taking.
This advisory includes selected information only and may not include all side effects of this medicine or interactions with other medicines. Ask your healthcare provider or pharmacist for more information or if you have any questions.
Keep all medicines out of the reach of children.
Do not share medicines with other people.
