Sevelamer, made simple.
Sevelamer, also sold under the brand name Renvela, is a medicine that lowers high phosphorus in people on dialysis. It has one rule that decides whether it works at all: it must be taken with meals. This guide explains how it works and how to take it. A Mississippi pharmacist wrote it for you.
This guide is here to teach you. It is not medical advice, and it does not replace your doctor or pharmacist. Always do what your doctor tells you, and ask a pharmacist before you change how you take any medicine.
Print this guide for your fridgeWhat sevelamer is and why your doctor gave it to you
Sevelamer is a medicine that lowers high phosphorus in your blood. It is sold as a generic called sevelamer, and under the brand name Renvela. They are the same medicine.
Phosphorus is a mineral that comes from food. Healthy kidneys clear the extra. When the kidneys fail and a person is on dialysis, phosphorus builds up, and over time too much phosphorus harms the bones and the blood vessels.
Sevelamer is called a phosphate binder. It keeps phosphorus from the food you eat from getting into your blood in the first place.
The simple version: sevelamer is taken with meals to soak up phosphorus from your food, so it leaves your body instead of building up and harming your bones and blood vessels.
How sevelamer works
Sevelamer stays in your gut and is not absorbed into your blood.
When you eat, phosphorus is released from your food in your intestine. If sevelamer is there at the same time, it grabs that phosphorus and holds onto it.
The bound phosphorus then leaves your body in your bowel movements instead of being absorbed. This is exactly why timing matters: sevelamer can only catch phosphorus from a meal if it is in your gut while you are eating that meal. Taken without food, it has nothing to do.
Your dose, and the meal rule
Sevelamer comes as tablets, and also as a powder for those who cannot swallow tablets. Your doctor decides your dose and your pharmacist checks it. This page will not tell you what dose to take.
Here is the rule that matters most: take sevelamer with every meal. It is usually taken three times a day, with breakfast, lunch, and dinner. Taking it three times a day with meals controls phosphorus much better than taking it once a day.
Swallow the tablets whole. Do not crush, chew, or break them. If you take the powder form, stir it vigorously into water, it will not fully dissolve, and drink the whole glass within 30 minutes.
Timing, and what to do if you miss a dose
Sevelamer is tied to your meals. Take it with each meal, as your doctor prescribed. The most common mistake is taking it without food, or at bedtime with no meal, which simply does not work.
Sevelamer can also bind some other medicines and reduce how well they are absorbed, so some medicines need to be spaced apart from it.
If you miss a dose:
- If you skip a whole meal, skip that dose of sevelamer too. It has nothing to work on without food.
- Take your next dose with your next full meal, as normal.
- Never take two doses at once to catch up.
- If you take thyroid medicine or certain other medicines, your pharmacist will tell you how many hours to separate them from sevelamer. Ask, and we will map it out.
Side effects, what is normal and what is not
Common, and usually mild.
- Nausea, or some stomach upset.
- Loose stools, or constipation.
- Gas, or a feeling of fullness.
Call your doctor if you notice:
- Nausea or vomiting that does not settle.
- Constipation with trouble passing stool.
- Muscle cramps, tingling, or twitching, which can be signs of low calcium.
Go to the emergency room right away if:
- You have severe stomach pain, a swollen or bloated belly, and you have stopped having bowel movements. A blockage in the bowel is rare but serious and needs care now.
What to be careful with
Sevelamer can bind some other medicines in your gut and lower how much of them you absorb. The ones that matter most are medicines that need to stay in a steady range.
Thyroid medicine is the clearest example. If you take thyroid medicine, keep it well separated from sevelamer, often by about 4 hours, and your pharmacist will confirm the exact window for you. The blood thinner warfarin and certain other medicines may also need spacing or closer monitoring.
The simple rule: before you start or stop any medicine or supplement, tell your pharmacist you take sevelamer. Every single time, so the timing can be checked.
One reassuring note: unlike some older phosphate binders, sevelamer does not add calcium to your body, which avoids the problem of calcium building up too high.
What it costs
The cost is different for every person, because every insurance plan is different.
Here is the honest way to find your price. If you pay cash, call Fairview and we will give you a price for your situation. If you have private insurance, there may be a coupon or a savings program from the maker of the drug that helps lower your cost, and we will check if one is available for you. The best step is to let a pharmacist look at your plan. We do this for every patient.
Do not let cost make you skip doses. Call us first. There is almost always something we can do.
There is also a generic version of many medicines. The generic is the same medicine. Ask your pharmacist if a generic is a good fit for you.
What should be checked
Sevelamer works best alongside the regular blood tests that are already part of dialysis care.
Your doctor should check, now and then:
- Your phosphorus level, to see that the dose is working.
- Your calcium level, since sevelamer does not add calcium.
- How your bowels are doing.
Your pharmacist should:
- Make sure you know to take it with every meal.
- Set the timing gap for thyroid medicine and any other medicine that needs it.
- Check whether the generic is the better cost choice for you.
- Help with cost and assistance programs.
At Fairview, we keep an eye on our sevelamer patients. If a refill is running late, we call you, and we make sure your medicine timing is set up to work.
Special situations
Take it with food, every time.
This is the heart of using sevelamer well. It only works on phosphorus from a meal, so it has to be in your gut while you eat. Taken on an empty stomach or at bedtime with no food, it does nothing. Tie each dose to a meal.
If you take thyroid medicine.
Sevelamer can bind thyroid medicine and stop it from working properly. Keep your thyroid medicine well separated from sevelamer. Your pharmacist will give you the exact gap, often around 4 hours. This is important, do not let the two land together.
Brand versus generic.
Generic sevelamer is widely available and is the same medicine as the brand Renvela. For most people the generic is the sensible, lower-cost choice. Ask your pharmacist what works best with your plan.
If you take blood thinner.
If you take the blood thinner warfarin, tell your doctor when sevelamer is started or changed. Your blood test for warfarin may need a closer look while things settle.
Cost should never be the reason you stop.
The generic keeps cost down for most people, and it is generally well covered. If cost is still a worry, call Fairview and we will help you find the lowest price.
How Fairview helps sevelamer patients
When you fill sevelamer at Fairview, here is what you get. This is normal care for us, not something extra.
At your first fill:
- We make sure you know to take it with every meal.
- We set the timing gap for thyroid medicine and anything else that needs it.
- We check whether the generic is the better choice for your cost.
- We answer your questions before you leave.
At every refill:
- We check your file for any new medicines.
- We check that you are refilling on time.
- We confirm your medicine timing still works.
On our own, without being asked:
- If a refill is late, we call you.
- If a new medicine needs spacing from sevelamer, we tell you.
- We check your cost at every fill to keep it as low as possible.
Questions people ask about sevelamer
It lowers high phosphorus in people with chronic kidney disease on dialysis. When the kidneys fail, phosphorus builds up and can harm the bones and blood vessels. Sevelamer keeps phosphorus from food out of your blood.
Have a question about your sevelamer? Ask a pharmacist who knows it well.
Sevelamer is simple once two habits are in place: take it with every meal, and keep thyroid medicine separated from it. Fairview makes both easy. If something made you wonder, ask us. Moving your prescription to us takes one phone call.