The patient was only given the liquid portion DTAP/IPV of Pentacel, not the powdered portion of ActHIB, with no reported adverse event;Initial information was received on 19-Oct-2021 regarding an unsolicited valid non-serious case received from a Physician, other health professional and consumer via Medical Information - 00819125.   This case involves a 2 month-old male patient who was supposed to receive DIPHTHERIA/TETANUS/5 HYBRID AC PERTUSSIS/IPV(VERO)/HIB(PRP/T) VACCINE [PENTACEL (VERO)] but the patient was only given the liquid portion of DTAP/IPV, not the powdered portion of Act-HIB(Product preparation issue).  The patient's past medical history, medical treatment(s), vaccination(s) and family history were not provided.  Concomitant medications included HEPATITIS B VACCINE; PNEUMOCOCCAL VACCINE CONJ and ROTAVIRUS VACCINE for prophylactic vaccination.  On 23-Sep-2021, the patient received 0.5 mL [Standard; total] dose of suspect DIPHTHERIA/TETANUS/5 HYBRID AC PERTUSSIS/IPV(VERO)/HIB(PRP/T) VACCINE (lot number and expiry date not reported) via an intramuscular route at the right thigh for prophylactic vaccination for prophylactic vaccination.  Batch number of Pentacel Liquid - U6899AA; Expiry Date: 21-May-2022 and batch number of Pentacel powder- UJ425AA ; Expiry Date: 21-May-2022.  It was reported "The MA asks how the powdered potion of Act-HIB can be administered and if it will be valid and count as a part of the Pentacel dose. MA asks if the powdered Act-HIB portion is safe to use since it has been out at room temperature below 77F since 23Sep2021. MA asking how to proceed after only administering the diluent of Pentacel to a child. MA states that a patient, was supposed to receive Pentacel on 23-Sep-2021. The patient was only given the liquid portion of DTAP/IPV, not the powdered portion of Act-HIB. It was not noticed that the Act-HIB portion was not given until today, 19-Oct-2021".  Short dose - lyophilized; Happened with diluent or product? Product; What volume of diluent were able to extract from the diluent vial? 0.5mL given to patient out of diluent vial (DTAP/IPV) given; Was all of the diluent taken from the vial? Yes, but powder (Act-HIB was not administered); Was there any bubbles or foaming when extracting the product? Not reported; Was there a lot of foam after reconstitution? There was no reconstitution; Did observe any changes in pellet or diluent volume prior to reconstitution? Not reported; Ask syringe brand, syringe size (1, 3 or 5 cc, etc.), gauge (20-25 gauges) and type (regular or safety). Not reported; Were the needles or syringes (or both) changed out after withdrawing the diluent or after reconstitution of the lyophilized product, prior to injection? No reconstitution; For Act-HIB or Pentacel, was needle positioned correctly in channel of Act-HIB stopper. No reconstitution; Must obtain lot numbers for diluent and powdered vaccine if possible. Did the issue occur before or after the mixing of the two components? No reconstitution; If the issue occurred before the mixing, did the problem concern the powder vial or the diluent vial? Powder vial.  It was a case of an actual medication error due to inappropriate reconstitution technique (latency was on same day).  At the time of report, no adverse event reported.  Outcome of event was unknown.  This suspected adverse reaction report is submitted and classified as a medication error solely and exclusively to ensure the marketing authorization holder's compliance with the requirements set out in the Directive 2001/83/EC and Module VI of the Good Pharmacovigilance Practices. The classification as a medical error is in no way intended, nor should it be interpreted or construed as an allegation or claim made by the marketing authorization holder that any third party has contributed to or is to be held liable for the occurrence of this medication error.  There will no information available on batch number for Pentacel.