One of the side effects of taking Viagra is blood vessels constriction; this is why most men experience a mild headache or dizziness after using this drug. A recent study from McGill University in Canada sought to determine whether or not this side effect is also present in blood donors, following their weekly dose of Viagra. The researchers, led by Dr. Charles Horsman, questioned 55 donors about any changes in their mental or physical status following their weekly donation, and about any side effects they may have experienced. The results of the study were published in April 2012 in the journal Clinical Biochemistry.
Although the sample size is fairly small, the results of the study suggest that donors may not be experiencing the same degree of headache or dizziness after donating blood as they are prior to their weekly dose of sildenafil.
Study Limitations
One of the major limitations of this study is represented by its small sample size. Even though this is a common problem with medical research involving human subjects, it is still a significant shortcoming, especially when dealing with a side effect as subjective as headache or dizziness. Another significant shortcoming of the study is that the sample consisted almost entirely of male blood donors. It would be interesting to see if other demographics, such as women or elderly individuals, experience different levels of headaches or dizziness following their donations. These limitations, however, do not diminish the relevance of the results obtained by the researchers. Indeed, even though the sample size was relatively small, it provided the researchers with some interesting data that may be useful in future studies involving larger populations and demographics.
In the study, the donors were administered a dose of Viagra (50 mg) one hour prior to their blood donation, in order to ensure that the drug was still active in their systems at the time of the donation. It is possible that different results would be obtained if the donors were administered the drug more than an hour before their blood donation, or if they skipped a dose, and then took the drug prior to their next scheduled donation. The researchers cannot, however, rule out the possibility of these variations resulting from the natural course of the drug or from other confounding factors present in the donors’ lifestyles.
The fact that this is a case study means that it is fairly easy for researchers to conduct a new study addressing this question. More data needs to be collected before we can make any conclusions about whether or not it is safe for blood donors to take Viagra after their weekly blood donation. Until more data is available, however, it would be unwise for blood donors to come off of their prescription without first consulting their physician.
Takeaway
Even though the sample size of this study is fairly small, the results obtained are still interesting and deserve our attention. They suggest that it may be safe for some individuals to take Viagra after donating blood, and that further studies should be conducted in order to determine the conditions under which this is and is not the case. This knowledge could eventually lead to more effective methods to prevent or treat various complications following blood donations, and possibly even to new drugs, supplements, or therapies that could enhance the health of blood donors.