Appropriate medical treatment and supervision should always be readily available in case of a rare anaphylactic reaction following the administration of the vaccine.
Additionally, live measles vaccine and live mumps vaccine are produced in chick embryo cell culture. Persons with a history of anaphylactic, anaphylactoid, or other immediate reactions (e.g. hives, swelling of the mouth and throat, difficulty breathing, hypotension, or shock) subsequent to egg ingestion may be at an enhanced risk of immediate‐type hypersensitivity reactions. The potential risk‐to‐benefit ratio should be carefully evaluated before considering vaccination in such cases.
Due caution should be employed in the administration of ProQuad to persons with individual or family history of convulsions, or a history of cerebral injury. The physician should be alert to the temperature elevation that may occur following vaccination (see Adverse Reactions).
Individuals less than 12 months of age who are vaccinated with a measles‐containing vaccine during measles outbreaks or for other reasons may fail to respond to the vaccine due to the presence of circulating antibodies of maternal origin and/or immaturity of the immune system (see Dosage & Administration and Pharmacology: Pharmacodynamics under Actions).
This vaccine contains 16 mg of sorbitol as an excipient. Patients with rare hereditary problems of fructose intolerance should not take this vaccine.
Vaccine recipients should avoid use of salicylates for 6 weeks after vaccination with ProQuad as Reye syndrome has been reported following the use of salicylates during wild‐type varicella infection.
Vaccination with ProQuad may not result in protection in all vaccine recipients.
Transmission: Excretion of small amounts of the live attenuated rubella virus from the nose or throat has occurred in the majority of susceptible individuals 7 to 28 days after vaccination. There is no confirmed evidence to indicate that such virus is transmitted to susceptible persons who are in contact with the vaccinated individuals. Consequently, transmission through close personal contact, while accepted as a theoretical possibility, is not regarded as a significant risk; however, transmission of the rubella vaccine virus to infants via breast milk has been documented without any evidence of clinical disease (see Use in Pregnancy & Lactation).
There are no reports of transmission of the more attenuated Enders' Edmonston strain of measles virus or the Jeryl Lynn strain of mumps virus from vaccine recipients to susceptible contacts.
Post‐marketing experience with Varicella Vaccine live (Oka/Merck) suggests that transmission of varicella vaccine virus may rarely occur between healthy vaccine recipients (who develop or do not develop a varicella‐like rash) and contacts susceptible to varicella, as well as high‐risk individuals susceptible to varicella (see Adverse Reactions).
High‐risk individuals susceptible to varicella include: immunocompromised individuals (see Contraindications), pregnant women without documented positive history of varicella (chickenpox) or laboratory evidence of prior infection, newborn infants of mothers without documented positive history of varicella or laboratory evidence of prior infection.
Vaccine recipients should attempt to avoid, whenever possible, close association with high‐risk individuals susceptible to varicella for up to 6 weeks following vaccination. In circumstances where contact with high‐risk individuals susceptible to varicella is unavoidable, the potential risk of transmission of the varicella vaccine virus should be weighed against the risk of acquiring and transmitting wild‐type varicella virus.
Thrombocytopenia: This vaccine should be given subcutaneously to individuals with thrombocytopenia or any coagulation disorder because bleeding may occur following an intramuscular administration in these individuals.
In clinical trials, no cases were reported regarding the development or worsening of thrombocytopenia in individuals vaccinated with ProQuad. Cases of thrombocytopenia have been reported in post‐marketing experience after primary vaccination with ProQuad. In addition, cases of thrombocytopenia have been reported after primary vaccination or revaccination with measles vaccine; measles, mumps, and rubella vaccine; and varicella vaccine. Post‐marketing experience with live measles, mumps, and rubella vaccine indicates that individuals with current thrombocytopenia may develop more severe thrombocytopenia following vaccination. In addition, individuals who experienced thrombocytopenia following the first dose of a live measles, mumps, and rubella vaccine may develop thrombocytopenia with repeat doses. Serologic status may be evaluated to determine whether or not additional doses of vaccine are needed. The risk‐to‐benefit ratio should be carefully evaluated before considering vaccination with ProQuad in such cases (see Adverse Reactions).
Febrile seizures: In the 5‐ to 12‐day timeframe after the administration of the first dose of quadrivalent measles, mumps, rubella and varicella vaccines in children, an increased risk of febrile seizure was observed compared to concomitant administration of measles, mumps, rubella and varicella vaccines (see Adverse Reactions and Pharmacology: Pharmacodynamics under Actions).
Other: Vaccination may be considered in patients with selected immune deficiencies where the benefits outweigh the risks (asymptomatic HIV patients, IgG subclass deficiencies, congenital neutropenia, chronic granulomatous disease, and complement deficiency diseases).
Immunocompromised patients who have no contraindication for this vaccination (see Contraindications) may not respond as well as immunocompetent patients; therefore, some of these patients may acquire measles, mumps, rubella, or varicella in case of contact, despite appropriate vaccine administration. These patients should be monitored carefully for signs of measles, parotitis, rubella, and varicella.
Post‐exposure prophylaxis: No clinical data are available for ProQuad administered after exposure to measles, mumps, rubella, or varicella. However, post‐exposure prophylaxis for varicella and measles has been demonstrated with Varicella Vaccine live (Oka/Merck) and the measles‐containing vaccines manufactured by Merck & Co., Inc., respectively.
Interference with laboratory tests: See Interactions.
Effects on ability to drive and use machines: No studies on the effects on the ability to drive or use machinery have been performed. ProQuad is expected to have no or negligible influence on the ability to drive and use machines.