Cases of thrombosis reported after vaccination with AstraZeneca are one in 300,000. "The risk of cerebral venous thrombosis is more frequent with contraceptives, which is 2%, and nobody stops taking contraceptives," says the head of the stroke unit at Vall d'Hebron Hospital, who also explains that behind women who have suffered thrombosis after taking contraceptives there is "an underlying coagulation problem".
The thromboses reported by AstraZeneca's vaccine - which they have named "vaccine-induced prothrombotic immune thrombocytopenia (VIPIT)" - resemble heparin-induced thrombosis, although it is, as with the vaccine, "a rare complication". "It is stated in the drug's data sheet, but it is not a reason not to use the drug or the vaccine," says Molina. "It is much more frequent with heparin - approximately every 80,000 cases - than with the vaccine, but it has been detected in clinical trials and is treated. The drug is not withdrawn because the benefits far outweigh the problem," he adds. He adds that the risk of thrombosis if you get covid is higher. "The combination of stroke and covid is one of the worst there is," he says. "These complications happen, and if you look at any drug's package leaflet you get scared, but it should be stated and documented for the information of patients," adds Molina, who insists that the benefit of the vaccine against the coronavirus is "much higher than the small percentage that may suffer thrombotic processes". "People are concerned about the contradictory information, and rightly so, but the message should be one of reassurance because this is part of normal clinical practice: all drugs and vaccines have side effects, they are evaluated and we move on," he explains.