anxiety; the cricopharyngaus Muscle spasm; muscle tighteness; Patient started having trouble breathing 28 hours after receiving the first vaccine dose / Felt like i couldn't breathe as if my throat wasn't open all the way; This spontaneous case was reported by a consumer and describes the occurrence of DYSPNOEA (Patient started having trouble breathing 28 hours after receiving the first vaccine dose / Felt like i couldn't breathe as if my throat wasn't open all the way), ANXIETY (anxiety), MUSCLE SPASMS (the cricopharyngaus Muscle spasm) and MUSCLE TIGHTNESS (muscle tighteness) in a 40-year-old female patient who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 032B21A and 05YC21A) for COVID-19 vaccination.     Concurrent medical conditions included Hay fever, Allergy to antibiotic (Allergy to Biaxin (felt like I could no breath)) in July 1998, Allergy to antibiotic (Allergy to Dynacin (felt like I could no breath)) in 2001, Allergy to chemicals (Allergy to Decongestants(Rash)) in 2008 and Allergy to antibiotic (Allergy to Doxycycline (Nausea)) in 2017. Concomitant products included DESOGESTREL, ETHINYLESTRADIOL (KARIVA) for Birth control.   On 27-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) 1 dosage form. On 27-May-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular) dosage was changed to 1 dosage form. On 28-Apr-2021, the patient experienced DYSPNOEA (Patient started having trouble breathing 28 hours after receiving the first vaccine dose / Felt like i couldn't breathe as if my throat wasn't open all the way). On an unknown date, the patient experienced ANXIETY (anxiety), MUSCLE SPASMS (the cricopharyngaus Muscle spasm) and MUSCLE TIGHTNESS (muscle tighteness). The patient was treated with CETIRIZINE HYDROCHLORIDE (ZYRTEC R) (oral) from 29-Apr-2021 to 28-May-2021 at a dose of 1 dosage form once a day and OMEPRAZOLE (PRILOSEC [OMEPRAZOLE]) for Muscle spasm, at a dose of 20 mg. At the time of the report, DYSPNOEA (Patient started having trouble breathing 28 hours after receiving the first vaccine dose / Felt like i couldn't breathe as if my throat wasn't open all the way), MUSCLE SPASMS (the cricopharyngaus Muscle spasm) and MUSCLE TIGHTNESS (muscle tighteness) had not resolved and ANXIETY (anxiety) had resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 30-Apr-2021, Chest X-ray: normal (normal) Normal. On 30-Apr-2021, Electrocardiogram: normal (normal) Normal. On 30-Apr-2021, Oxygen saturation: 100 (normal) Not provided. On an unknown date, Blood test: negative (Negative) blood test done for blood clot. On an unknown date, Endoscopy: normal (normal) Normal.     For mRNA-1273 (Moderna COVID-19 Vaccine) (Intramuscular), the reporter did not provide any causality assessments.   Patient went to urgent care on 30-Apr-2021 at 8am. The doctor could not say if this was due to vaccine or what was happening. She advised to continue with Zyrtec for few days. But still patient was feeling of not being able to breathe completely. Patient saw specialist who mentioned it may be anxiety. Patient's throat was examined by scope by ENT doctor. ENT doctor said he did not think it was anxiety. He said sometimes cricopharyngeal muscle will spasm and tighten causing such symptom.  Doctor prescribed 40 mg of Prilosec which the patient will take if the breathing issue not resolved.   Most recent FOLLOW-UP information incorporated above includes: On 25-Jul-2021: Significant Follow up - patient's demographics updated , medical history added , lab tests added , concomitant and treatment information added , event outcome updated