You cannot donate blood if:
Your hemoglobin level is lower than the minimum level of hemoglobin needed to donate blood (12.0 g/dL for females and 13.0 g/dL for males);
You have low or high blood pressure;
You have any blood-related diseases;
You are taking certain medicines like blood-thinners or antibiotics;
You were vaccinated recently;
You are tested positive for hepatitis B, hepatitis C or HIV infection;
You are pregnant; or
You have tattoos or piercings.
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