Usage
This combination of immunoglobulins and toxoids is primarily used for passive and active immunization against diphtheria, tetanus, pertussis (whooping cough), and Haemophilus influenzae type b (Hib) infections. Diphtheria immune globulin provides immediate but temporary passive immunity, while the toxoids and Hib polysaccharide stimulate the body’s active immune response for long-term protection.
It falls under the pharmacological classification of vaccines and immunoglobulins.
Mechanism of Action: The immune globulin component provides pre-formed antibodies for immediate protection against diphtheria. The toxoids (inactivated toxins) of tetanus, diphtheria, and pertussis stimulate the immune system to produce antibodies against these bacterial toxins, while the Hib capsular polysaccharide induces an immune response targeted against Hib bacteria.
Alternate Names
This combination does not have one single international non-proprietary name (INN) because it’s a combination product. Instead, the components are individually identified by their respective INN:
- Diphtheria Immune Globulin (Human): Diphtheria Antitoxin
- Haemophilus influenzae Type B Capsular Polysaccharide: Hib PRP or Hib polysaccharide
- Pertussis Toxoid: Pertussis Vaccine (Acellular Component), or Pertussis toxoid (Whole-cell Component)
- Tetanus Toxoid: Tetanus Vaccine (Toxoid)
The combination itself may be referred to by names reflecting the combined components, such as DTP-Hib or DTaP-Hib combination vaccine.
Brand Names: Infanrix Hexa, Pentacel, and Vaxelis (these may contain additional components such as IPV and Hepatitis B vaccine). Note that brand names and availability can vary by region.
How It Works
Pharmacodynamics: The diphtheria antitoxin neutralizes the diphtheria toxin circulating in the body, preventing it from binding to its target cells. Tetanus and diphtheria toxoids induce the production of antibodies that neutralize their respective toxins. The pertussis toxoid and Hib polysaccharide activate specific B cells to generate antibodies against pertussis bacteria and Hib bacteria, facilitating their destruction by other components of the immune system (opsonization, complement activation).
Pharmacokinetics: The diphtheria immune globulin is administered intramuscularly (IM) or intravenously (IV) providing rapid access to the circulation. Tetanus and diphtheria toxoids and Hib polysaccharide are typically administered IM. They are gradually absorbed from the injection site, processed by antigen-presenting cells, and presented to lymphocytes to initiate the immune response. Antibody titers typically peak within weeks after vaccination. Antibodies are distributed throughout the body fluids and can cross the placenta to provide passive immunity to the fetus. Elimination of antibodies occurs gradually over time. The toxoids and Hib polysaccharide themselves are broken down and eliminated by the body.
Mode of Action at the Cellular/Molecular Level: Toxoids are recognized by T helper cells and B cells as foreign antigens. This interaction stimulates B cells to differentiate into plasma cells and produce specific IgG antibodies against the toxoid. The Hib polysaccharide similarly triggers B cells to produce specific antibodies, but it primarily induces a T-cell independent B cell response, which generates IgM antibodies.
Receptor Binding, Enzyme Inhibition, Neurotransmitter Modulation: The mechanism of action of this combined product primarily involves antibody-mediated neutralization of toxins and opsonization of bacteria, rather than direct receptor binding, enzyme inhibition, or neurotransmitter modulation.
Elimination Pathways: Antibodies are primarily eliminated through protein catabolism.
Dosage
Standard Dosage
Dosage for this combination product can vary depending upon the specific product and local vaccination schedules. General guidelines as per the sources are below:
Adults:
A tetanus-diphtheria (Td) or Tdap booster is recommended every 10 years for adults. Women are recommended to receive a dose of Tdap during each pregnancy. Diphtheria immune globulin is used in adults only for treatment of diphtheria.
Children:
DTaP-Hib combinations are generally given as a primary series of three doses at 2, 4, and 6 months of age, followed by a booster dose around 15-18 months. Local guidelines may recommend additional boosters during childhood.
Special Cases:
Dosage adjustments may be required based on specific patient factors and are best determined by consulting regional vaccination guidelines and the specific product information.
Clinical Use Cases
The described combination is mainly used for preventive immunization, not in the specific clinical contexts you provided (intubation, surgical procedures, mechanical ventilation, etc.). Tetanus prophylaxis may be given using tetanus toxoid (or immunoglobulin in certain cases) in wound management following injury.
Dosage Adjustments
Dosage adjustments may be necessary in individuals with immunodeficiencies or specific medical conditions. Consult regional guidelines or specific product information for recommendations.
Side Effects
Common Side Effects
- Pain, redness, and swelling at the injection site
- Fever
- Irritability or fussiness (in infants)
- Drowsiness or fatigue
Rare but Serious Side Effects
- Allergic reactions (anaphylaxis)
- Seizures (very rare)
Long-Term Effects
Long-term side effects are rare with this combination of toxoids and immunoglobulins.
Adverse Drug Reactions (ADR)
Serious ADRs are extremely rare but may include allergic reactions (anaphylaxis) and, very rarely, neurological complications.
Contraindications
- Severe allergic reaction (anaphylaxis) to any component of the vaccine
- Encephalopathy within 7 days of a previous dose of pertussis-containing vaccine (for pertussis component)
Drug Interactions
- Immunosuppressive drugs may reduce the immune response to the vaccine components.
- Concomitant administration of tetanus immune globulin or diphtheria antitoxin should be at a separate injection site.
- Several chemotherapeutic agents can potentially interact with the Hib component, and their use should be carefully evaluated.
Pregnancy and Breastfeeding
Tdap is recommended during pregnancy, preferably between 27 and 36 weeks gestation. Data suggest no harmful effects of the Hib vaccine during pregnancy, but it’s not routinely recommended unless there is a specific risk. There is no conclusive information from sources whether any of the components are excreted in breast milk. Consult regional guidelines for the latest recommendations.
Drug Profile Summary
- Mechanism of Action: Provides passive immunity against diphtheria (with immune globulin) and induces active immunity against diphtheria, tetanus, pertussis and Hib.
- Side Effects: Commonly injection site reactions and fever. Rarely allergic reactions.
- Contraindications: Hypersensitivity, encephalopathy after prior pertussis vaccination.
- Drug Interactions: Immunosuppressants, tetanus/diphtheria antitoxin.
- Pregnancy & Breastfeeding: Tdap is recommended during pregnancy.
- Dosage: As per vaccination schedule for specific age groups.
- Monitoring Parameters: Observe for allergic reactions or other adverse events following vaccination.
Popular Combinations
DTaP is often combined with IPV (inactivated poliovirus vaccine) and Hepatitis B vaccine (e.g., Infanrix Hexa, Vaxelis, and some formulations of Pentacel).
Precautions
- Screen for contraindications and previous reactions before administration.
- Monitor patient after administration for immediate adverse events.
- Consult with a specialist for individuals with specific risk factors.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Diphtheria Immune Globulin + Haemophilus Influenzae Type B Capsular Polysaccharide + Pertussis Toxoid + Tetanus Toxoid?
A: The dosage varies based on age and specific product. Refer to the respective vaccination schedule and product information.
Q2: Can this combination be given during pregnancy?
A: Tdap is recommended during pregnancy. Consult local guidelines regarding Hib vaccination in pregnancy.
Q3: What are the common side effects in infants?
A: Common side effects include pain, redness, swelling at the injection site, fever, irritability, and drowsiness.
Q4: What should I do if a patient experiences an allergic reaction?
A: Immediately administer epinephrine and provide supportive care as needed.
Q5: Can this vaccine be given to immunocompromised individuals?
A: Consult specialist advice as the immune response may be suboptimal in immunocompromised individuals.
Q6: Are there any contraindications for the pertussis component?
A: Yes. Contraindications include a history of encephalopathy within 7 days of a previous dose of pertussis-containing vaccine.
Q7: Can this vaccine be given with other vaccines?
A: Yes, but it should be administered at a separate injection site from tetanus immune globulin or diphtheria antitoxin. Other vaccines can typically be co-administered at the same visit.
Q8: How long does the protection from this combination last?
A: The duration of protection varies by component. Booster doses are required to maintain immunity.
Q9: What is the difference between DTaP and DTwP?
A: DTaP contains acellular pertussis antigens, while DTwP contains whole-cell pertussis. DTaP is generally preferred due to a lower risk of side effects.
