PhosLo: What It Is, How It Works, and What You Need to Know

When your kidneys can't remove excess phosphorus, PhosLo, a calcium acetate-based phosphate binder used to lower blood phosphorus levels in people with kidney failure. Also known as calcium acetate, it binds to the phosphorus in your food so your body doesn't absorb it—instead, it passes out in your stool. Without treatment, too much phosphorus can weaken bones, damage blood vessels, and raise your risk of heart problems. That’s why PhosLo is a common part of treatment for people on dialysis or with advanced chronic kidney disease.

PhosLo doesn’t work alone. It’s taken with meals, right when you eat, so it can grab phosphorus from your food before your body absorbs it. If you skip a dose or take it at the wrong time, it won’t help. It’s not a cure—it’s a tool. And like any tool, it only works if used correctly. People on dialysis often take it three to five times a day, depending on their diet and blood levels. Your doctor will check your phosphorus levels regularly to make sure the dose is right. Too little, and your levels stay high. Too much, and you risk getting too much calcium, which can cause other problems like calcification in your arteries.

PhosLo is one of several phosphate binders. Others include sevelamer, a non-calcium, non-aluminum phosphate binder often used when calcium levels need to be tightly controlled, and lanthanum, a chewable tablet that binds phosphorus without adding calcium. Each has pros and cons. PhosLo is cheaper, but it adds calcium. Sevelamer doesn’t raise calcium, but it’s more expensive and can cause stomach upset. Your choice depends on your blood levels, diet, budget, and how your body reacts.

Many people on PhosLo also take vitamin D supplements or calcimimetics like cinacalcet to help manage calcium and phosphorus together. These aren’t alternatives to PhosLo—they work with it. You can’t just take one and forget the others. Kidney disease management is a balancing act, and PhosLo is one piece of that puzzle. It’s not glamorous, but it’s necessary. Skipping it because it’s inconvenient or because you don’t feel sick is risky. High phosphorus doesn’t always cause symptoms until it’s already doing damage.

What you’ll find below are real-world guides on how PhosLo fits into daily life—how to take it right, what to eat with it, how to avoid interactions, and how it compares to other options. You’ll also see how it connects to broader topics like kidney disease, diet control, and medication safety. No fluff. No theory. Just what matters when you’re managing this every day.