Interferon beta-1a and Tetanus Immune Globulin

• Generic Name: interferon beta-1a
• Dosage Forms: n.a.
• Other Brand Names: Avonex, Rebif, Avonex Prefilled Syringe, Avonex Pen, Rebif Rebidose, Rebif Rebidose Titration Pack, Rebif Titration Pack

Interferon beta-1a is used to treat relapsing multiple sclerosis (MS) in adults.

interferon beta-1a will not cure MS, it will only decrease the frequency of relapse symptoms.

Interferon beta-1a may also be used for purposes not listed in this medication guide.

• Generic Name: tetanus immune globulin
• Dosage Forms: n.a.
• Other Brand Names: HyperTET S/D

Postexposure prophylaxis of tetanus in individuals with tetanus-prone wounds who have previously received <3 doses of a preparation containing tetanus toxoid adsorbed or whose tetanus vaccination status is uncertain.

TIG provides temporary passive immunity against tetanus. It is not a substitute for active immunization with a preparation containing tetanus toxoid adsorbed and is not a substitute for adequate medical and surgical care of contaminated or potentially contaminated wounds. (See General under Dosage and Administration.)

Tetanus is a potentially fatal disease caused by a neurotoxic exotoxin produced by Clostridium tetani (tetanospasmin). C. tetani spores are ubiquitous in the environment and are found in soil and in animal (e.g., horses, sheep, cattle, dogs, cats, rats, guinea pigs, chickens) and human intestinal tracts. The spores can contaminate open wounds, especially puncture wounds or those with devitalized tissue; anaerobic wound conditions allow the spores to germinate and produce exotoxins that disseminate through the blood and lymphatic system. Neonatal tetanus occurs in infants born under nonsterile conditions to women inadequately vaccinated against tetanus; infection usually involves a contaminated umbilical stump and occurs because infant does not have passively acquired maternal antibodies against tetanus. Obstetric tetanus occurs within 6 weeks after delivery or termination of pregnancy because of contaminated wounds or abrasions or unclean deliveries or abortions. Generalized tetanus is characterized by rigidity and convulsive muscle spasms that usually involve the jaw (lockjaw) and neck and then become generalized. Tetanus occurs worldwide, almost exclusively in individuals who are unvaccinated or inadequately vaccinated against the disease. An average of 31 cases reported each year in the US from 2000 through 2007 (case fatality rate 10%); 20 cases reported in 2003. Most cases of tetanus in the US occur following acute injuries or wounds (puncture wounds, lacerations, abrasions) and usually occur in adults ≥40 years of age; however, an increase in the disease has been reported in younger adults (e.g., heroin abusers).

Tetanus-prone wounds include wounds contaminated with dirt, feces, soil, or saliva; puncture wounds; avulsions; and wounds resulting from crushing, burns, or frostbite. Tetanus also has been associated with apparently clean, superficial wounds, surgical procedures, insect bites, animal bites, dental infections, chronic sores and infections, and IV drug abuse. Tetanus is not transmitted person-to-person.

TIG is not necessary for tetanus postexposure prophylaxis in patients with clean, minor wounds (regardless of their immunization status) or for patients with tetanus-prone wounds who have previously received ≥3 doses of a preparation containing tetanus toxoid adsorbed.

In the event of injury and possible exposure to tetanus, the need for active immunization against tetanus with or without passive immunization with TIG depends on the individual’s vaccination status and the likelihood of contamination with tetanus bacilli (e.g., condition of wound, source of contamination). See Table 1 for ACIP guidelines regarding tetanus postexposure prophylaxis.

Tetanus toxoid, reduced diphtheria toxoid and acellular pertussis vaccine adsorbed (Tdap). A dose of Tdap is preferred to a dose of Td in adolescents and adults 11 through 64 years of age who have not previously received a dose of Tdap. Use Td in individuals in this age group who previously received a dose of Tdap.

Tetanus and diphtheria toxoids adsorbed (Td). Td is used in adults, adolescents, and children ≥7 years of age. For children 6 weeks through 6 years of age, DTaP usually is indicated, but DT can be used if pertussis antigens are contraindicated. Monovalent tetanus toxoid adsorbed generally is used only when preparations containing tetanus and diphtheria antigens and preparations containing tetanus, diphtheria, and pertussis antigens are contraindicated or unavailable.

If only 3 doses of tetanus toxoid fluid (no longer commercially available in the US) have been received previously, a fourth dose should be given as a preparation containing tetanus toxoid adsorbed.

Yes, if it has been >10 years since last dose of tetanus toxoid-containing preparation.

Yes, if it has been >5 years since last dose of tetanus toxoid-containing preparation; more frequent booster doses not needed and can accentuate adverse effects.

Adapted from the Recommendations of the Immunization Practices Advisory Committee (ACIP) on prevention of diphtheria, tetanus, and pertussis published in MMWR Recomm Rep. 1991; 40(RR-10):1-28, MMWR Recomm Rep. 2006; 55(RR-3):1-43, and MMWR Recomm Rep. 2006; 55(RR-17):1-37.

Any individual whose tetanus vaccination status is unknown or uncertain should be considered to have had no previous doses of tetanus toxoid adsorbed.

Anti-infectives are not indicated for tetanus postexposure prophylaxis.

Treatment of Tetanus

Treatment of tetanus. Used in conjunction with an anti-infective active against C. tetani (e.g., metronidazole, penicillin G) and with sedatives and muscle relaxants as needed.

Treatment of neonatal tetanus in conjunction with an anti-infective active against C. tetani (e.g., penicillin G).

Evidence of effectiveness of TIG in the treatment of active tetanus infection is limited and optimum dosage not established. Although TIG can neutralize unbound exotoxin, it does not affect toxin already bound to nerve endings.

Recovery from tetanus does not result in naturally-acquired tetanus immunity. As soon as possible, initiate or complete active immunization against tetanus using a preparation containing tetanus toxoid adsorbed.