Serum/plasma concentration of proton pump inhibitor (lansoprazole)

Why This Test Is Done

Your healthcare provider may order this test if you’re taking lansoprazole (a proton pump inhibitor) to treat conditions like acid reflux, ulcers, or excessive stomach acid. It helps ensure the medication is at an effective concentration in your bloodstream.

What to Expect Before the Test

No special preparation is usually needed. You may have blood drawn from a vein in your arm, similar to other blood tests. If you’re on a long-term medication like lansoprazole, your provider may recommend testing at a specific time (e.g., before or after doses) to get the most accurate results.

What the Results Mean

Results are typically reported as a concentration in micrograms per milliliter (mcg/mL). While reference ranges vary by lab, lower-than-expected levels might suggest your dose isn’t strong enough, while very high levels could indicate side effects or improper dosing. Your provider will interpret these results in the context of your medical history and symptoms.

Common Reasons for Testing

Doctors may order this test if you’re experiencing side effects (like nausea, fatigue, or unusual bruising), if your symptoms don’t improve with treatment, or if you’re switching medications.