Muscle contractions, twitching, spasms: with pain in the right leg, buttock, calf, difficult to get in a car and drive, cannot sit in chair for less than 15 seconds, after the second vaccine.; Muscle contractions, twitching, spasms: with pain in the right leg, buttock, calf, difficult to get in a car and drive, cannot sit in chair for less than 15 seconds, after the second vaccine.; Muscle contractions, twitching, spasms: with pain in the right leg, buttock, calf, difficult to get in a car and drive, cannot sit in chair for less than 15 seconds, after the second vaccine.; Muscle contractions, twitching, spasms: with pain in the right leg, buttock, calf, difficult to get in a car and drive, cannot sit in chair for less than 15 seconds, after the second vaccine.; Muscle contractions, twitching, spasms: with pain in the right leg, buttock, calf, difficult to get in a car and drive, cannot sit in chair for less than 15 seconds, after the second vaccine.; This is a spontaneous report from a contactable consumer (patient's mother). A 37-year-old male patient received second dose of BNT162B2 (PFIZER-BIONTECH COVID-19 mRNA VACCINE, Solution for injection) via an unspecified route of administration, to his right arm on 24May2021 around 10 AM (Lot number: EW0185, NDC number/Expiry date: Unknown) as single dose for Covid-19 immunization. The patient's medical history and concomitant medications were not reported. The patient previously took first dose of BNT162B2 to his right arm on 03May2021 in the morning (Lot number: EW0165, NDC number/Expiry date: Unknown) as single dose for Covid-19 immunization. On 26May2021, the patient experienced muscle contractions, twitching, spasms: with pain in the right leg, buttock, calf, difficult to get in a car and drive, cannot sit in chair for less than 15 seconds, after the second vaccine. Caller confirmed that her son had his second shot of the Pfizer vaccine, reclarified as the Covid vaccine. Caller stated that last Tuesday until now, her son had been having muscle contractions from his legs to his buttocks, and the back of his foot, had to be messaged. Muscle contractions and pain from his leg to his buttock, and the back of his foot: later reclarified as muscle contractions, muscle twitching, and muscle spasms of the right leg and buttock, and calf. Caller stated when her son woke up in the morning, he had pain with the muscle contractions. Caller stated that her son did not have any health insurance, at that time. Some patient details reclarified later in the call, by the caller's son when reported on himself. Caller's son stated that it was hard for him to get in a car or sit in a chair, for less than 15 seconds. Caller's son stated that he could not drive. Reclarified, patient stated that his muscle contractions, spasms also feels like they were twitching. Caller notified that Pfizer was unable to provide medical advice but might have resources to help answer some questions. In this situation, the caller was encouraged to go to an Urgent Care, should his symptoms become concerning. Additional information had been requested. Reporter seriousness for muscle contractions, twitching, spasms: with pain in the right leg, buttock, calf, difficult to get in a car and drive, cannot sit in chair for less than 15 seconds, after the second vaccine: Unspecified. Outcome of the events was not recovered.  No follow-up attempts are needed. No further information is expected.