Most medications do not prevent you from donating blood. Common medications such as those used to control blood pressure, birth control pills and over-the-counter medications do not affect your eligibility. If you have recently taken antibiotics, you must have completed the course prior to donating.
Yes, a tooth infection can cause a headache. Also, be aware that certain sinus conditions can mask as tooth problems.
These symptoms include redness, inflammation (swelling), constant bad breath, toothaches, tender and/or bleeding gums. A gum infection is different from a tooth infection because the gums are not as effectively controlled by means of brushing, flossing and rinsing. However, healthy gums and healthy teeth do go hand-in-hand and do benefit each other when proper oral hygiene is used.