Favirab

Indications

Rabies immunoglobulin (RIG) is used, together with a full course of rabies vaccine, for people who have had a severe (category III) exposure to an animal that may have rabies: bites or scratches that break the skin, licks on broken skin or mucous membranes, or any bat exposure. It gives immediate protection while the vaccine has time to work. Products may be made from human plasma or from horse (equine) serum.

How It Works

RIG contains ready-made antibodies that attach to and neutralise the rabies virus at the wound site before it can enter the nerves. This is called passive immunisation. The vaccine then makes the body produce its own long-lasting antibodies, which takes about 7 to 14 days.

Dosage and Administration

RIG is given only by a doctor or nurse. The dose depends on body weight and the type of product, as prescribed. As much as possible is infiltrated in and around the wounds, and any remainder may be injected into a muscle away from the vaccine site. It is given once, ideally with the first vaccine dose, and no later than 7 days after the first vaccine dose. Wash the wound well with soap and running water for 15 minutes as soon as possible.

Interactions

RIG must not be injected into the same site or with the same syringe as the rabies vaccine, and the dose should not exceed what is recommended, as too much can reduce the vaccine response. It may reduce the response to some live vaccines (such as measles), so these may need to be delayed.

Contraindications

• There is no absolute contraindication after a real rabies exposure, as rabies is almost always fatal.
• People with a previous severe reaction, or with allergy to horse serum (for equine products), need special care and close monitoring.
• People who already completed full rabies vaccination before do not need RIG.

Side Effects

Pain, swelling and redness at the injection site and mild fever are common. Equine products can occasionally cause serum sickness (rash, joint pain and fever about a week later) or allergic reactions.

Get urgent medical help for swelling of the face or throat, difficulty breathing, widespread rash or feeling faint after the injection, and always seek care immediately after any animal bite.

Pregnancy and Lactation

Pregnancy and breastfeeding are not reasons to delay RIG after an exposure, because rabies is fatal. It is given when needed.

Precautions and Warnings

The patient is observed after injection, with emergency treatment ready for allergic reactions. Complete the full vaccine schedule exactly as advised. Report bites from dogs, cats, monkeys, jackals or other animals promptly.

Overdose

Too much RIG may weaken the response to the vaccine. The doctor may adjust the vaccine plan.

Therapeutic Class

Immunoglobulin, passive immunising agent (anti-rabies).

Storage

Store in a refrigerator at 2 to 8°C, do not freeze, protect from light. Hospital product: handle as directed on the pack.