Diphtheria Toxoid + Haemophilus Influenzae Type B Capsular Polysaccharide + Inactivated Polio Vaccine + Pertussis Toxoid + Tetanus Toxoid

Usage

This combination vaccine is prescribed for active immunization against diphtheria, tetanus, pertussis (whooping cough), poliomyelitis (polio), and invasive diseases caused by Haemophilus influenzae type b (Hib) bacteria. It is primarily used in infants and young children. This vaccine falls under the pharmacological classification of vaccines/immunological agents.

The mechanism of action involves stimulating the immune system to produce antibodies against the toxoids (inactivated toxins) of diphtheria and tetanus, the antigens of pertussis and poliovirus, and the capsular polysaccharide of Hib. These antibodies provide long-term active immunity against these diseases.

Alternate Names

This combination vaccine often goes by various names depending on the specific formulation and manufacturer. There isn’t a single universal international nonproprietary name (INN). Commonly, it’s referred to as DTaP-IPV-Hib. Sometimes Hepatitis B is added as well.

Brand names vary by region and manufacturer. Examples include Infanrix hexa and Vaxelis.

How It Works

Pharmacodynamics: The vaccine components stimulate an immune response, specifically the humoral immunity, leading to the production of antibodies against the respective pathogens. This immune response mimics natural infection without causing the diseases themselves. Memory B-cells are also created, enabling the body to respond quickly and effectively upon subsequent exposure to the pathogens.

Pharmacokinetics: The vaccine is administered intramuscularly (IM). The toxoids and polysaccharides are adsorbed onto aluminum salts (adjuvants) which enhance the immune response by creating a depot at the injection site, allowing for slow release and prolonged antigen presentation. The antigens are then taken up by antigen-presenting cells, initiating the immune response. Antibody titers peak within a few weeks of vaccination and persist for several years, providing sustained protection.

Dosage

Standard Dosage

Children: The primary vaccination series typically consists of three doses given at 2, 4, and 6 months of age. A booster dose is recommended at 18 months and between 4 and 6 years of age.

Adults: The combination vaccine in this form is not typically administered to adults. Adults may receive separate tetanus, diphtheria, and pertussis (Tdap) or Td boosters.

Special Cases: Dosage adjustments in special populations (elderly, renal/hepatic impairment) are not relevant as this vaccine is primarily for infants and young children.

Clinical Use Cases

The primary use case is routine childhood immunization. There are no specific clinical uses for this combination vaccine in settings like intubation, surgical procedures, mechanical ventilation, ICU, or emergency situations.

Side Effects

Common Side Effects:

Pain, redness, and swelling at the injection site, mild fever, irritability, drowsiness, loss of appetite.

Rare but Serious Side Effects:

High fever (over 104°F), seizures, allergic reactions (e.g., hives, difficulty breathing), persistent crying (more than 3 hours).

Contraindications

Severe allergic reaction to a previous dose of the vaccine or any of its components, encephalopathy (brain damage) within 7 days of a previous dose of a pertussis-containing vaccine.

Drug Interactions

Immunosuppressive therapy may reduce the immune response to the vaccine. Concomitant administration with other vaccines is generally safe, but timing may be adjusted as per national vaccination schedules.

Pregnancy and Breastfeeding

This combination vaccine is not intended for pregnant or breastfeeding women.

Drug Profile Summary

• Mechanism of Action: Stimulates the immune system to produce antibodies against diphtheria, tetanus, pertussis, polio, and Hib.
• Side Effects: Common: Injection site reactions, fever, irritability. Rare: High fever, seizures, allergic reactions.
• Contraindications: Severe allergic reaction to previous dose, encephalopathy following previous pertussis vaccine.
• Drug Interactions: Immunosuppressants.
• Pregnancy & Breastfeeding: Not indicated.
• Dosage: Three primary doses at 2, 4, and 6 months of age; boosters at 18 months and 4-6 years.
• Monitoring Parameters: Observe for adverse reactions, especially allergic reactions and high fever.

Popular Combinations

This combination vaccine itself represents a commonly used combination for childhood immunization. It may be administered along with other childhood vaccines, such as those for measles, mumps, and rubella (MMR) according to recommended schedules.

Precautions

Standard precautions for vaccine administration should be followed, including ensuring proper storage, aseptic technique, and patient monitoring for immediate adverse reactions. Defer vaccination in individuals with acute moderate or severe febrile illness.

FAQs (Frequently Asked Questions)

Q1: What is the recommended dosage for DTaP-IPV-Hib?

A: Three doses of 0.5 mL are given intramuscularly at 2, 4, and 6 months of age, followed by boosters at 18 months and 4-6 years.

Q2: Can DTaP-IPV-Hib be given with other vaccines?

A: Yes, it can be given concurrently with other vaccines, although different injection sites should be used. Consult national immunization schedules for specific recommendations.

Q3: What are the most common side effects?

A: The most common side effects are local reactions at the injection site (pain, redness, swelling) and mild systemic reactions (fever, irritability).

Q4: Who should not receive DTaP-IPV-Hib?

A: Children with a history of severe allergic reaction to a previous dose or any component of the vaccine, or encephalopathy within 7 days of a prior dose of pertussis-containing vaccine, should not receive DTaP-IPV-Hib.

Q5: What should I do if my patient experiences a serious adverse reaction?

A: Immediately report any serious adverse events to the appropriate health authorities. Provide supportive care as needed.

Q6: How is DTaP-IPV-Hib stored?

A: The vaccine should be stored refrigerated at 2-8°C and protected from light. Do not freeze.

Q7: Can DTaP-IPV-Hib be given to premature infants?

A: Yes, DTaP-IPV-Hib can be administered to premature infants according to the chronological age, starting at 2 months of age.

Q8: What is the difference between DTaP and Tdap?

A: DTaP is given to children under 7 years of age and contains higher concentrations of diphtheria and pertussis antigens. Tdap is given to older children and adults and contains lower concentrations of these antigens.

Q9: How long does immunity last after the primary series?

A: Immunity wanes over time, which is why booster doses are recommended.