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Marfan syndrome: the signs, what causes it and who gets it, getting a diagnosis, treatment, and living with it
For anyone with long arms, legs and fingers, loose joints, or a chest that caves in or sticks out who wonders whether it is Marfan syndrome; anyone with Marfan syndrome in the family, or a relative who died young of a heart problem nobody could explain; and anyone just told that they or their child have it. The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS, part of the NIH) says Marfan syndrome is a genetic disorder of connective tissue that can affect the skeleton, the eyes, the heart and blood vessels, the skin and the lungs, and that research and advances in treatment allow people with it to live long, productive lives. This page passes on, by name, what NIAMS says: the signs and the problems that can develop; the gene and who gets it; the history, the exam and the tests; the medicines by kind, other treatments and surgery; and living with it. It builds the words to say to a provider, and prints a card for the visit.
Right now
- Sudden, severe pain in your chest, back or belly, fainting, or suddenly not being able to catch your breath: call 911, and say that you have Marfan syndrome (ours). NIAMS says an aneurysm of the aorta is a life-threatening emergency if its wall tears or ruptures, and names a collapsed lung (pneumothorax) among the problems that can develop.
- Sudden flashes of light, a shower of new floaters, or a shadow or curtain over part of your sight: see an eye doctor or go to an emergency room today (ours). NIAMS names retinal detachment among the problems that can develop.
- Thinking about suicide: call or text 988, any time.
More help
- Related: Scoliosis · Back pain · Pain, bones and joints.
- Heart, lungs and sleep: Heart attack · High blood pressure · Sleep apnea · Quit smoking.
- Eyes and teeth: Eye care · Dental care.
- Family: Pregnancy and a new baby.
- Day to day: Symptom diary · Medicines list · Anxiety.
- Care and costs: When you need a doctor and can’t pay · When medicine costs too much · Get ready for the appointment.
- In a crisis: Help right now (988, 911). All our free tools.
Pain, a bone or a joint, and not sure this is the right page? The pages on this site for back pain, arthritis, pain that lasts, headaches, broken bones and sickle cell, on one list.
This page and its wording were written with AI (Claude) for Scarlet Beast (our AI policy). No doctor, nurse or therapist has reviewed it. The facts were read on October 16, 2026 on NIAMS’s Marfan Syndrome page, both parts: Overview, Symptoms, & Causes and Diagnosis, Treatment, & Steps to Take (NIH, last reviewed October 2023), and on its shorter Spanish twin, Síndrome de Marfan (June 2020). Ours: calling 911 for sudden, severe pain in the chest, back or belly, fainting, or sudden trouble breathing, and saying you have Marfan syndrome; seeing an eye doctor or going to an emergency room today for sudden flashes, new floaters or a curtain over your sight; that the signs alone do not mean you have it; that nobody causes it; telling each provider about your family; not stopping a prescribed medicine on your own; asking a pharmacist about an over-the-counter medicine; writing things down and keeping a wallet note; asking what a test or treatment would change, its risks and what it costs; 988; and the order of the steps. What we left out: any medicine’s name or dose, any treatment NIAMS does not name, any diet, supplement, remedy or product, related conditions NIAMS does not describe, and NIAMS’s research pages. This page saves nothing and loads no trackers.