About 10 or 11 days after receiving 1st dose, he had pain in his thighs that radiated to his back.; allergic reaction; He didn't get 2nd dose because of allergic reaction; On day 6, he found out that he had a blood clot in calf of his right leg upon doing ultrasound,He isn't sure if that was a second clot in thighs.; Then on day 4, his leg was getting very painful,About 10 or 11 days after receiving 1st dose, he had pain in his thighs that radiated to his back.; Within 5-10 minutes of receiving 1st dose, his lips started to swell; His tongue started to swell.; He had shortness of breath.; This spontaneous case was reported by a consumer and describes the occurrence of THROMBOSIS (On day 6, he found out that he had a blood clot in calf of his right leg upon doing ultrasound,He isn't sure if that was a second clot in thighs.) in a 62-year-old male patient who received mRNA-1273 (Moderna COVID-19 Vaccine) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.     Concomitant products included DICLOXACILLIN and LOSARTAN for an unknown indication.    On 30-Apr-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) 1 dosage form. On 30-Apr-2021, the patient experienced LIP SWELLING (Within 5-10 minutes of receiving 1st dose, his lips started to swell), SWOLLEN TONGUE (His tongue started to swell.) and DYSPNOEA (He had shortness of breath.). On 03-May-2021, the patient experienced PAIN IN EXTREMITY (Then on day 4, his leg was getting very painful,About 10 or 11 days after receiving 1st dose, he had pain in his thighs that radiated to his back.). On 05-May-2021, the patient experienced THROMBOSIS (On day 6, he found out that he had a blood clot in calf of his right leg upon doing ultrasound,He isn't sure if that was a second clot in thighs.) (seriousness criterion medically significant). On an unknown date, the patient experienced BACK PAIN (About 10 or 11 days after receiving 1st dose, he had pain in his thighs that radiated to his back.), HYPERSENSITIVITY (allergic reaction) and PRODUCT DOSE OMISSION ISSUE (He didn't get 2nd dose because of allergic reaction). The patient was treated with DIPHENHYDRAMINE HYDROCHLORIDE (BENADRYL [DIPHENHYDRAMINE HYDROCHLORIDE]) ongoing since an unknown date at an unspecified dose and frequency. At the time of the report, THROMBOSIS (On day 6, he found out that he had a blood clot in calf of his right leg upon doing ultrasound,He isn't sure if that was a second clot in thighs.), LIP SWELLING (Within 5-10 minutes of receiving 1st dose, his lips started to swell), SWOLLEN TONGUE (His tongue started to swell.), DYSPNOEA (He had shortness of breath.), PAIN IN EXTREMITY (Then on day 4, his leg was getting very painful,About 10 or 11 days after receiving 1st dose, he had pain in his thighs that radiated to his back.), BACK PAIN (About 10 or 11 days after receiving 1st dose, he had pain in his thighs that radiated to his back.), HYPERSENSITIVITY (allergic reaction) and PRODUCT DOSE OMISSION ISSUE (He didn't get 2nd dose because of allergic reaction) outcome was unknown.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On 05-May-2021, Ultrasound scan: blood clot in calf (abnormal) blood clot in calf.     The action taken with mRNA-1273 (Moderna COVID-19 Vaccine) (Unknown) was unknown.       Treatment includes ultrasound was reported.  Concomitant includes medicinal marijuana was reported.  Patient received his 1st dose on 30Apr2021. Within 5-10 minutes of receiving 1st dose, his lips started to swell. His tongue started to swell. He had shortness of breath. Within 15-20 minutes, swelling of tongue went away after taking Benadryl. Then on day 4, his leg was getting very painful. On day 6, he found out that he had a blood clot in calf of his right leg upon doing ultrasound. About 10 or 11 days after receiving 1st dose, he had pain in his thighs that radiated to his back. He isn't sure if that was a second clot in thighs. He didn't get 2nd dose because of allergic reaction. He mentioned that there was 1 doctor that got blood clot after receiving moderna vaccine.  Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.; Sender's Comments: Based on the current available information and temporal association between the use of the product and the start date of the events, a causal relationship cannot be excluded.