I am experiencing dizziness/lightheadedness directly from lisinopril. what could be possible causes of this besides side effects?

Check BP: A low BP might do it, check to see your reading. Discuss your symptoms with your prescriber.

Dizziness and drugs: You should speak to the physician (p) who ordered the Lisinopril about your problem. At the very least, your blood pressure should be checked to make sure it is not too low. If it isn't, you may need some blood work to check your electrolytes and blood count. If you are anemic, that could be the cause of your dizziness. See your p and get a check up to find the answer to your question.