If you've started a GLP-1 medication like Wegovy, Ozempic, or Zepbound and things have slowed down, you're not imagining it. Constipation is one of the most commonly reported side effects of these drugs — and after 65, it's worth paying a little extra attention to. The good news: for most people it eases with time, and there's a lot you can do about it. Here's what's normal, what tends to help, and the warning signs that mean it's time to call your doctor.

Why GLP-1 medications cause constipation

GLP-1 drugs work partly by slowing how quickly your stomach empties — that's a big part of why you feel full longer and eat less. But the same slowdown carries through your whole digestive tract, which can leave stool harder, drier, and less frequent. Constipation and other stomach complaints are listed as common side effects in the FDA Medication Guides that come with these medications. It's often most noticeable in the first few weeks and after each dose increase, then tends to settle as your body adjusts.

Why it can hit harder after 65

Older adults are already more prone to constipation, and a GLP-1 stacks on top of the usual reasons:

  • Other medications. Many common senior prescriptions slow the gut on their own — certain blood-pressure drugs (calcium channel blockers), iron and calcium supplements, some pain medicines, and bladder-control drugs. Add a GLP-1 and the effect compounds.
  • Eating and drinking less. A GLP-1 sharply reduces appetite, so many people take in less fluid and fiber — exactly the wrong direction for staying regular.
  • Slower digestion and less movement. Both come naturally with age, and both make constipation more likely.
  • Higher stakes. In older adults, untreated constipation can progress to a painful stool impaction that sometimes needs medical treatment — which is why it's better to stay ahead of it than to wait and see.

What tends to help — but check with your doctor or pharmacist first

Because you may be taking other medications, run any new supplement or laxative past your pharmacist before you start. It's a free, two-minute conversation, and they can flag interactions with your other prescriptions.

  • Fluids come first. Relief usually starts with drinking enough water through the day. If you're on a fluid restriction for your heart or kidneys, ask your doctor what's right for you rather than guessing.
  • Add fiber gradually. Building up fiber slowly — from foods or a supplement your doctor okays — is gentler than a sudden jump, which can worsen bloating. Our free GLP-1 food list is a good starting point.
  • Move a little more. Even gentle daily walking helps keep things moving.
  • Don't ignore the urge. Answering it promptly, and giving yourself unhurried time, makes a real difference.
  • Ask about over-the-counter options. Your doctor or pharmacist may suggest a stool softener or an osmotic laxative such as polyethylene glycol — but the right choice depends on your other medicines and your kidney function, which is exactly why it's a conversation to have rather than a guess.
  • Watch dose changes. If constipation flares right after a dose increase, mention it — sometimes a slower titration schedule helps.

Warning signs: when to call your doctor

Reach out to your doctor promptly if you have:

  • No bowel movement for several days, especially with belly pain or bloating
  • Severe or worsening abdominal pain — pain that is intense or spreads to your back needs urgent attention, as it can signal a more serious problem
  • Vomiting, or a hard, swollen belly
  • Blood in your stool, or black, tarry stools
  • Constipation that doesn't improve after a couple of weeks of the steps above

These can be signs of an impaction or a blockage, which need medical care. Don't try to push through severe symptoms at home.

Keep a simple log so your doctor can help

"I've been backed up lately" is hard for a doctor to act on. Jotting down when you have a bowel movement, how much you're drinking, and when symptoms flare turns a vague complaint into a clear picture — and makes it far easier to tell whether a recent dose change is the culprit. Any notebook works; if you'd rather track it on your phone, a daily symptom log does the same job.

The bottom line

Constipation on a GLP-1 is common, usually temporary, and very manageable — but after 65 it's worth treating early, keeping your fluids up, and looping in your doctor or pharmacist before reaching for a new laxative. Staying ahead of it keeps a minor nuisance from becoming a real problem.

Still deciding whether a GLP-1 is right for you? See our overview of GLP-1 side effects in seniors and, if nausea is also bothering you, how to settle GLP-1 nausea. To check whether Medicare will help cover your medication, take our 2-minute eligibility quiz.

Sources: FDA Wegovy (semaglutide) Prescribing Information — lists constipation among the most common adverse reactions and notes severe constipation, including fecal impaction; and NIDDK: Symptoms & Causes of Constipation (National Institute of Diabetes and Digestive and Kidney Diseases) on how medications and other factors cause constipation. Always follow the instructions that come with your specific medication and your doctor's advice.