Yes, all 3 shots of the Pfizer Covid vaccine contain the same active ingredient, which is the mRNA that codes for the spike protein of the coronavirus. This means that the vaccine works by teaching the body's immune system to recognize and fight against the spike protein, which is found on the surface of the coronavirus.
The Pfizer Covid vaccine is designed to be given in a two-dose series, with the second dose administered 3 weeks after the first. However, recent studies have shown that a third dose may be necessary to provide additional protection against the coronavirus, especially as new variants emerge. This third dose is essentially a booster shot to help strengthen the body's immune response to the virus.
It is recommended to get all 3 shots of the Pfizer Covid vaccine from the same location for consistency and to ensure proper documentation of your vaccination record. However, if you are unable to do so, you can receive the third dose from a different location as long as you provide proof of your first 2 doses.
At this time, there is not enough data to support mixing and matching different types of Covid vaccines. It is recommended to stick with the same type of vaccine for all 3 doses, unless otherwise advised by a healthcare professional.
It is possible to experience more side effects with the third dose of the Pfizer Covid vaccine, as the body's immune response may be stronger after receiving 3 doses. However, the side effects are typically mild and temporary, and are a sign that the vaccine is working to build immunity against the coronavirus.