Hi Mary,
Aldactone, lisinopril, and atenolol can be used in combination to lower blood pressure. The combination of aldactone and lisinopril has the potential to caused elevated potassium levels in the body; however, this is a commonly used combination of medications. As long as your physician is monitoring you regularly, it is a fine regimen to use. You may also find this link helpful: http://www.healthcentral.com/high-blood-pressure/find-drug-226568-73.html.
Thank you for your question!
Jill