Several commonly used medications carry risks of thromboembolism and vascular problems that do not prevent their use.

The European Medicines Agency (EMA) has taken its time, but finally, after weeks of uncertainty, has come out: the drug Vaxzevria, formerly known as Astrazeneca’s Covid-19 vaccine, is linked to the occurrence of rare side effects, particularly of venous sinus thrombosis. However, the opinion is that the benefits outweigh the risks, so he continues to recommend its use in a decision that will continue to be confusing for many.

The appearance of clots in the cerebral venous system is a very rare incident, on the order of 1-1.3 cases / 100,000 inhabitants per year as confirmed by the Spanish Society of Neurology (SEN), so its incidence after vaccination drew the attention of the health authorities. This would be at one case per million vaccinated, a side effect that should be classified as “very rare” and that pales in the face of the public health benefits associated with achieving group immunity to Covid-19 as soon as possible.

On the other hand, it is necessary to differentiate ‘secondary effects’ from ‘adverse effects’ related to a ‘health episode’. This implies, as explained to EL ESPAÑOL Joan Carles Reverter, president of the Spanish Society of Thrombosis and Haemostasis (SETH) that it can only be established a temporal association between drug administration and the appearance of these thrombi, but not a cause-effect relationship.

Although the EMA points to those under 60 years of age, which is why Spain is considering excluding them from vaccination with this drug, the appearance of these accidents may simply respond to the fact that This is the age group that has received the most AstraZeneca doses, as it is reserved for groups such as police officers and teachers. On the other hand, health professionals insist, all medicines, even those in common use, carry a minimum threshold of risk that is specified in the package leaflet and that the consumer accepts, many times without knowing that something else is being put into the mouth. ‘dangerous’ than the unjustly maligned vaccine.


It is undoubtedly one of the most famous and used oral medications, and in fact a daily dose has been recommended to prevent such prevalent diseases as cancer and hypertension. Scientific evidence, however, qualifies the risk-benefit ratio and recommends it only in very specific cases because this habitual consumption can do more harm than good.

A study published in The Lancet in 2017 it pointed out that solo in the United Kingdom Are accounted for about 20,000 hemorrhages and about 3,000 deaths per year associated with the practice of taking an aspirin every day.

Oral contraceptives

The famous Contraceptive ‘pill’ is not recommended for women over 35 years of age, with obesity and smokers, precisely because of a small risk of thromboembolism. The director of the Center for Pharmacovigilance of Castilla y León and the Center for Drug Safety Studies, Dr. Luis Martín Arias, regretted the interruption of the use of the vaccine in his community, stressing that in both cases the risk is minimal in comparison when contracting Covid-19

Thus, the specialist has highlighted that between 10 and 15 percent of people who suffer from covid suffer thrombi, while this occurs only with 0.1% of women who use oral contraceptives and it happens to only one of every 300,000 people who are vaccinated with AstraZeneca.


Drugs like prednisone can also cause this effect of thrombus or embolism, explained in The newspaper Maria Perelló, head of the medicine information center of the Official College of Pharmacists of Barcelona (COFB). The use from Oral corticosteroids would thus present a “certain risk” of thrombosis, highlighted the Spanish Society of Hematology and Hemotherapy (SEHH).

Corticosteroids, paradoxically, constitute a early treatment that has demonstrated efficacy in patients with Covid-19 in Intensive Care Units (ICU). According to a record prepared during the pandemic by the Anesthesiology and Resuscitation Services in Spain, reduce mortality rate by up to 14 points.


Drugs like tofacitinib, for the cases of rheumatoid arthritis, ulcerative colitis or immune diseases, they are other of those mentioned due to their possible thrombotic risk. It has been described risk of blood clots in the legs (deep vein thrombosis) or lungs (pulmonary thromboembolism) when there are risk factors (smoking, previous history of thrombosis, hormonal treatment, age, sedentary lifestyle).


Even the diuretic medications, in those people who have hypertension and who consume them in excess, they can cause a thrombosis, he declared to The newspaper the associate physician of the Obstetrics and Gynecology Service of the Vall d’Hebron Hospital (Barcelona), Itzíar García Ruiz. Beyond the type of medication, there is a “Patient group” most at risk of suffering thromboembolism: the elderly, sedentary, with some basic pathology and with high cholesterol.