double vision in his eyes when both eyes are open/ not able to drive/ diagnosed with myasthenia gravis; This spontaneous case was reported by a consumer and describes the occurrence of MYASTHENIA GRAVIS (double vision in his eyes when both eyes are open/ not able to drive/ diagnosed with myasthenia gravis) in a male patient of an unknown age who received mRNA-1273 (Moderna COVID-19 Vaccine) (batch nos. 039F21A, 024M20A and 027L20A) for COVID-19 vaccination.     No Medical History information was reported.   On 14-Jan-2021, the patient received first dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) .5 milliliter. On 10-Feb-2021, received second dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to .5 milliliter. On 30-Oct-2021, received third dose of mRNA-1273 (Moderna COVID-19 Vaccine) (unknown route) dosage was changed to .25 milliliter. On 05-Feb-2022,  after starting mRNA-1273 (Moderna COVID-19 Vaccine), the patient experienced MYASTHENIA GRAVIS (double vision in his eyes when both eyes are open/ not able to drive/ diagnosed with myasthenia gravis) (seriousness criterion medically significant). The patient was treated with PYRIDOSTIGMINE BROMIDE (MESTINON) for Myasthenia gravis, at an unspecified dose and frequency and IMMUNOGLOBULINS NOS (IMMUNOGLOBULIN I.V) (intravenous) for Myasthenia gravis, at an unspecified dose and frequency. At the time of the report, MYASTHENIA GRAVIS (double vision in his eyes when both eyes are open/ not able to drive/ diagnosed with myasthenia gravis) had not resolved.      DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Blood test: normal (normal) The test result so far had been negative for anything.. On an unknown date, Computerised tomogram: normal (normal) The test result so far had been negative for anything.. On an unknown date, Magnetic resonance imaging: normal (normal) The test result so far had been negative for anything..         No concomitant medications were reported.  Company comment: This spontaneous case concerns a male patient of unknown age with no reported medical history who experienced the unexpected, serious (medically significant) ADR of Myasthenia Gravis. The event occurred approximately 3 months and 6 days after receiving a dose of mRNA1273 as third dose (First booster) of the vaccine.  The patient developed double vision after receiving the mRNA1273 vaccine which has been ongoing for almost 3months. Patient undergone MRI, CT scan and blood work (unspecified tests) but the results were negative. The patient was eventually diagnosed with myasthenia gravis and was treated with Pyridostigmine bromide and IV Immunoglobulin infusions, but these did not provide any relief of symptom. He was then taken off those treatments. Patient did not had any muscle weakness, except for double vision which occurred when both eyes were open and not able to drive. Patient had received mRNA-1273 as primary series of vaccination and no adverse event was reported. The benefit-risk relationship of mRNA-1273 is not affected by this report   Reporter did not allow further contact; Reporter's Comments: The patient received his 1st booster dose of the Moderna COVID-19 vaccine on 30-Oct-2021. Everything seemed to be fine initially and the patient did not experience any side effects. However, on 05-Feb-2022, patient started developing double vision in his eyes. Currently it was going on for 3 months. He had been to many doctors, averaging about 2-3 doctors a week for the last 3 months. He had MRI, CT scan, and blood work done during some of these visits. All test results so far were negative for anything. His medical condition led to seek medical care and the patient consulted ER, family physician, 2 different neurologists, hematologist, and neuro ophthalmologist. The patient's HCPs diagnosed him with myasthenia gravis. However, even after getting treated with Mestinon and IVIg infusions, his symptoms did not subside. He was then taken off those treatments. He did not had any muscle weakness, but only the double vision. It occurred when both eyes were open. With either eye closed, he did not had double vision and could see better. It has been a hell for him for the past 3 months and also he was not even been able to drive. The patient did not experience any similar events in the past. The symptoms were stable.; Sender's Comments: This spontaneous case concerns a male patient of unknown age with no reported medical history who experienced the unexpected, serious (medically significant) ADR of Myasthenia Gravis. The event occurred approximately 3 months and 6 days after receiving a dose of mRNA1273 as third dose (First booster) of the vaccine.  The patient developed double vision after receiving the mRNA1273 vaccine which has been ongoing for almost 3months. Patient undergone MRI, CT scan and blood work (unspecified tests) but the results were negative. The patient was eventually diagnosed with myasthenia gravis and was treated with Pyridostigmine bromide and IV Immunoglobulin infusions, but these did not provide any relief of symptom. He was then taken off those treatments. Patient did not had any muscle weakness, except for double vision which occurred when both eyes were open and not able to drive. Patient had received mRNA-1273 as primary series of vaccination and no adverse event was reported. The benefit-risk relationship of mRNA-1273 is not affected by this report