PHQ-9: What It Is, How It’s Used, and What the Results Mean

When a doctor asks you to fill out the PHQ-9, a nine-question screening tool used to identify depression symptoms. It's also known as the Patient Health Questionnaire-9, and it’s one of the most common ways clinicians check for depression in everyday practice. You won’t find fancy jargon here—just nine plain questions about how you’ve felt over the past two weeks. No blood tests. No scans. Just your honest answers.

The PHQ-9 isn’t a diagnosis—it’s a starting point. It measures how often you’ve had symptoms like low mood, trouble sleeping, fatigue, or feeling worthless. Each answer is scored from 0 to 3, and the total tells your doctor how severe your symptoms might be. A score of 10 or higher often means moderate to severe depression, and that’s when treatment—like therapy or medication—usually gets discussed. It’s not perfect, but it’s fast, free, and backed by decades of real-world use in clinics and hospitals.

What makes the PHQ-9 so useful is how it connects to real treatment decisions. If your score is high, your doctor might look at your meds—like checking if an antidepressant is working, or if something like trimethoprim or thiazide diuretics could be making things worse. It also helps track progress. If you’re on levothyroxine for hypothyroidism, your mood might improve once your thyroid levels stabilize—and the PHQ-9 can show that change over time. Even when used with DMARDs for autoimmune disease, it helps separate physical fatigue from emotional burnout.

You’ll find that many of the articles below use the PHQ-9 as a reference point. Some talk about how antihistamines can make depression worse due to their anticholinergic effects. Others explain why certain pain relievers or antidepressants like vilazodone might cause side effects that mimic or worsen depression symptoms. Even the DASH diet comes up—not because it cures depression, but because nutrition affects brain chemistry, and the PHQ-9 helps track whether lifestyle changes are helping.

There’s no shame in taking the PHQ-9. It’s not a test you pass or fail. It’s a tool to help you get the right care. If you’ve been feeling off for weeks—not just stressed, but drained, hopeless, or disconnected—that score could be the key to finally getting help. Below, you’ll find real stories and data about how medications, lifestyle, and mental health intersect. Whether you’re asking about side effects, drug interactions, or how to talk to your doctor, these posts give you the facts you need to move forward.