Researchers will then compare the length of symptoms between the placebo and the antibiotic group. conditions: Community Acquired Pneumonia in Children conditions: Mycoplasma Pneumoniae conditions: Mycoplasma Pneumoniae Pneumonia studyType: INTERVENTIONAL phases: NA allocation: RANDOMIZED interventionModel: PARALLEL interventionModelDescription: This is a randomized, double-blind, placebo-controlled, multicenter, non-inferiority trial. primaryPurpose: TREATMENT masking: QUADRUPLE whoMasked: PARTICIPANT whoMasked: CARE_PROVIDER whoMasked: INVESTIGATOR whoMasked: OUTCOMES_ASSESSOR count: 376 type: ESTIMATED name: Azithromycin Pfizer® name: Placebo measure: Co-primary outcome: days to normalization of all vital signs measure: Co-primary outcome: community-acquired pneumonia(CAP)-related change in patient care status measure: Overall clinical outcome measure: Time (days) to normalization of CAP-related symptoms measure: Quality of Life (QoL) Assessment assessing impact of the child's pneumonia on the family's social and health-related well-being measure: Time (days) to return to daily routine measure: Incidence of Mp-associated extrapulmonary manifestations development in patients assessed by clinical examination and/or parent report measure: Length of hospital stay (LOS) measure: Number of unscheduled medical visits measure: Proportion of patients (re-)treated with antibiotics for any reason measure: Side effects/AEs/serious AE (SAE)s of investigational medicinal product (IMP) measure: Microbiological indicators sex: ALL minimumAge: 3 Years maximumAge: 17 Years stdAges: CHILD facility: Children's Hospital Aarau, Switzerland city: Aarau state: Aargau zip: 5001 country: Switzerland name: Henrik Köhler, Prof. Dr. med. role: CONTACT phone: 0041 62 838 41 41 email: Henrik.Koehler@ksa.ch name: Henrik Köhler, Prof. Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 47.39254 lon: 8.04422 facility: University of Basel Children's Hospital, Switzerland city: Basel state: Basel-Stadt zip: 4056 country: Switzerland name: Julia A Bielicki, PD Dr. Dr. med. role: CONTACT phone: 0041 61 704 12 12 email: julia.bielicki@ukbb.ch name: Julia A Bielicki, PD Dr. Dr. med. role: PRINCIPAL_INVESTIGATOR name: Ulrich Heiniger, Prof. Dr. med. role: SUB_INVESTIGATOR lat: 47.55839 lon: 7.57327 facility: Department of Pediatrics, Cantonal Hospital Graubuenden, Switzerland city: Chur state: Graubünden zip: 7000 country: Switzerland name: Beate Deubzer, Dr. med. role: CONTACT phone: 0041 81 256 61 11 email: beate.deubzer@ksgr.ch name: Beate Deubzer, Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 46.84986 lon: 9.53287 facility: Children's Hospital of Eastern Switzerland St. Gallen city: St. Gallen state: Saint Gallen zip: 9006 country: Switzerland name: Anita Niederer-Loher, Dr. med. role: CONTACT phone: 0041 71 243 71 11 email: anita.niederer@kispisg.ch name: Anita Niederer-Loher, Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 47.42391 lon: 9.37477 facility: Institute of Pediatrics of Southern Switzerland, EOC, Bellinzona, Switzerland city: Bellinzona state: Ticino zip: 6500 country: Switzerland name: Lisa Kottanattu, Dr. med. role: CONTACT phone: 0041 91 811 91 11 email: Lisa.Kottanattu@eoc.ch name: Lisa Kottanattu, Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 46.19278 lon: 9.01703 facility: Department of Pediatrics, Department Mother-Woman-Child, Lausanne University Hospital, Switzerland city: Lausanne state: Vaud zip: 1011 country: Switzerland name: Ludivine Coulon, Dr. med. role: CONTACT phone: 0041 21 314 11 11 email: Ludivine.Coulon@chuv.ch name: Ludivine Coulon, Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 46.516 lon: 6.63282 facility: Department of Pediatrics, Cantonal Hospital Winterthur, Switzerland city: Winterthur state: Zurich zip: 8401 country: Switzerland name: Andreas Jung, Dr. med. role: CONTACT phone: 0041 52 266 41 44 email: andreas.jung@ksw.ch name: Andreas Jung, Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 47.50564 lon: 8.72413 facility: University Children's Hospital Bern, Switzerland city: Bern zip: 3010 country: Switzerland name: Philipp Agyeman, PD Dr. med. role: CONTACT phone: 0041 31 632 21 11 email: Philipp.Agyeman@insel.ch name: Philipp Agyeman, PD Dr. med. role: PRINCIPAL_INVESTIGATOR name: Kristina Keitel, PD Dr. Dr. med. role: SUB_INVESTIGATOR lat: 46.94809 lon: 7.44744 facility: Department of Pediatrics, Fribourg Hospital, Switzerland city: Fribourg zip: 1708 country: Switzerland name: Petra Zimmermann, PD Dr. Dr. med. role: CONTACT phone: 0041 26 306 00 00 email: petra.zimmermann@unifr.ch name: Petra Zimmermann, PD Dr. Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 46.80237 lon: 7.15128 facility: Children's Hospital of Geneva, University Hospitals of Geneva, Switzerland city: Geneva zip: 1205 country: Switzerland name: Noémie Wagner, Dr. med. role: CONTACT phone: 0041 22 372 40 00 email: Noemie.Wagner@hcuge.ch name: Noémie Wagner, Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 46.20222 lon: 6.14569 facility: Children's Hospital of Central Switzerland, Switzerland city: Luzern zip: 6000 country: Switzerland name: Alex Donas, Dr. med. role: CONTACT phone: 0041 41 205 31 66 email: alex.donas@luks.ch name: Alex Donas, Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 47.05048 lon: 8.30635 facility: University Children's Hospital Zurich, Switzerland city: Zurich zip: 8032 country: Switzerland name: Michelle Seiler, PD Dr. med role: CONTACT phone: 0041 44 266 71 11 email: Michelle.Seiler@kispi.uzh.ch name: Michelle Seiler, PD Dr. med role: PRINCIPAL_INVESTIGATOR lat: 47.36667 lon: 8.54999 facility: Department of Pediatrics, Triemli Hospital Zurich, Switzerland city: Zurich zip: 8063 country: Switzerland name: Maren Tomaske, Prof. Dr. med. role: CONTACT phone: 0041 44 416 11 11 email: Maren.Tomaske@stadtspital.ch name: Maren Tomaske, Prof. Dr. med. role: PRINCIPAL_INVESTIGATOR lat: 47.36667 lon: 8.54999 hasResults: False