Taking Lipitor, a statin used to lower cholesterol, and blood pressure medication together can increase the risk of certain side effects. According to the Mayo Clinic [1], one of the possible interactions between statins like Lipitor and blood pressure medications is muscle pain or weakness.

A study published by the American Heart Association found that co-administration of statins and beta-blockers, a type of blood pressure medication, can increase the risk of muscle damage in some patients [2].

However, not all interactions are negative. A review of the literature by the National Institutes of Health suggests that co-administration of statins and certain blood pressure medications, such as angiotensin-converting enzyme (ACE) inhibitors, may actually help to improve renal function in patients with diabetes [3].

To mitigate the risk of adverse interactions, it's essential to talk to your doctor about your specific medication regimen and any concerns you may have.

Sources:
[1]https://www.mayoclinic.org/drugs-supplements/lipitor-atorvastatin-oral-route/description/drg-20069545
[2]https://www.ahajournals.org/doi/abs/10.1161/01.CIR.0000103025.76485.7C
[3]https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2938556/