Saturday she felt really sick and then she was sick all Saturday night; She thought it was from her not sleeping all night; bad mood swings; Then when woke up she was in a fog and started to have a break down and was angry.; she had a manic episode and "mental breakdown" that lasted three days/in a mania, mental breakdown; she had a manic episode and "mental breakdown" that lasted three days/in a mania, mental breakdown; Received Pfizer Covid booster; This is a spontaneous report received from contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient.  A 25 year-old female patient received bnt162b2 (BNT162B2), administered in arm right, administration date 03Dec2021 18:30 (Batch/Lot number: unknown) at the age of 25 years as dose number unknown (booster), single for covid-19 immunisation. Relevant medical history included: "bipolar disorder" (unspecified if ongoing), notes: previous dx of bipolar disorder, diagnosed when she was 18 years old. Concomitant medication(s) included: LITHIUM taken for bipolar disorder. Vaccination history included: Covid-19 vaccine (First Dose, manufacturer unknown), administration date: Apr2021, for COVID-19 immunization; Covid-19 vaccine (Second Dose, manufacturer unknown), administration date: May2021, for COVID-19 immunization. The following information was reported: IMMUNISATION (non-serious) with onset 03Dec2021 18:30, outcome "unknown", described as "Received Pfizer Covid booster"; MANIA (non-serious), MENTAL DISORDER (non-serious) all with onset 04Dec2021, outcome "recovering" and all described as "she had a manic episode and "mental breakdown" that lasted three days/in a mania, mental breakdown"; ILLNESS (non-serious), outcome "unknown", described as "Saturday she felt really sick and then she was sick all Saturday night"; INSOMNIA (non-serious), outcome "unknown", described as "She thought it was from her not sleeping all night"; MOOD SWINGS (non-serious), outcome "unknown", described as "bad mood swings"; FEELING ABNORMAL (non-serious), outcome "unknown", described as "Then when woke up she was in a fog and started to have a break down and was angry.".  Additional information: Patient diagnosed with Bipolar disorder when she was 18 years old. She has bipolar disorder and was in a mania for three days. She was fine before she got the covid booster and then after she had a mental breakdown for no reason. She takes Lithium for her bipolar disorder, 150mg tablet, three tablets in the morning and two tablets at night by mouth. Patient was ok after first two shots. With the booster she got really sick which she knows was normal. Saturday she felt really sick and then she was sick all Saturday night. Then when woke up she was in a fog and started to have a break down and was angry. She thought it was from her not sleeping all night and then this continued for another 2 days. She was not sure if it was from the vaccine or not. She finally feels a lot better today and she was having really bad mood swings. She does not know how to explain. She has not acted like that since before she got diagnosed. Getting into full recovery and feels better. Patient declined for any treatment, she made sure she was taking her meds and not missing a dose. She made sure to stay home not trying to interact with anyone. She could not think of the other medication she takes off the top of her head, it also helps with her mood.   The lot number for bnt162b2 was not provided and will be requested during follow up.