If you've had episodes of blood clots or pregnancy loss that aren't explained by known health conditions, your health care provider can schedule blood tests to check for clotting and for the presence of the antibodies associated with antiphospholipid syndrome.

To confirm a diagnosis of antiphospholipid syndrome, the antibodies must appear in your blood at least twice, in tests conducted 12 or more weeks apart.

You can have antiphospholipid antibodies and never develop signs or symptoms. A diagnosis of antiphospholipid syndrome is made only when these antibodies cause health problems.


If you have blood clots, standard initial treatment involves a combination of blood-thinning medications. The most common are heparin and warfarin (Jantoven). Heparin is fast-acting and delivered via injections. Warfarin comes in pill form and takes several days to take effect. Aspirin is also a blood thinner.

When you're taking blood thinners, you have an increased risk of bleeding episodes. Your doctor will monitor your dosage with blood tests to be sure your blood is capable of clotting enough to stop the bleeding of a cut or the bleeding under the skin from a bruise.

There is some evidence that other drugs might be helpful in treating antiphospholipid syndrome. These include hydroxychloroquine (Plaquenil), rituximab (Rituxan) and statins. More study is needed.

Treatment during pregnancy

It's possible to have a successful pregnancy if you have antiphospholipid syndrome, especially with treatment. Treatment usually involves heparin or heparin with aspirin. Warfarin isn't given to pregnant women because it can affect the fetus.

Clinical trials

Explore Mayo Clinic studies testing new treatments, interventions and tests as a means to prevent, detect, treat or manage this condition.

Self care

Depending on your treatment plan for antiphospholipid syndrome, there are other steps you can take to protect your health. If you take blood-thinning medications, take extra care to keep from injuring yourself and to avoid bleeding.

  • Avoid contact sports or other activities that could cause bruising or injury or cause you to fall.
  • Use a soft toothbrush and waxed floss.
  • Shave with an electric razor.
  • Take extra care when using knives, scissors and other sharp tools.
  • Women should avoid using estrogen therapy for contraception or menopause.

Food and dietary supplements

Certain foods and medications may affect how well your blood thinners work. Ask your health care provider for guidance about:

  • Safe dietary choices. Vitamin K can lessen the effectiveness of warfarin, but not other blood-thinners. You might need to avoid eating large amounts of vitamin K-rich foods such as avocado, broccoli, Brussels sprouts, cabbage, leafy greens and garbanzo beans. Alcohol can increase warfarin's blood-thinning effect. Ask your doctor if you need to limit or avoid alcohol.
  • Safe medications and dietary supplements. Certain medications, vitamins and herbal products can interact dangerously with warfarin. These include some pain relievers, cold medicines, stomach remedies or multivitamins, as well as garlic, ginkgo and green tea.

Preparing for your appointment

In most cases, complications of antiphospholipid syndrome — such as deep vein thrombosis (DVT), stroke or pregnancy loss — will prompt you to seek medical care. Depending on your complication, you'll likely see a specialist in vascular disease, obstetrics or hematology.

Here's some information to help you get ready for your appointment.

What you can do

Be aware of any pre-appointment restrictions. When you make the appointment, ask if there's anything you need to do in advance. Make a list of:

  • Your signs or symptoms and when they began
  • Key personal information, including major recent events or changes in your life
  • Key medical information, including other conditions or infections you have and family medical history, especially close relatives who've had antiphospholipid syndrome
  • All medications, vitamins and other supplements you take, including doses
  • Questions to ask your doctor

Take a family member or friend along, if possible, to help you remember the information you get.

For antiphospholipid syndrome, some questions to ask your doctor include:

  • What's the most likely cause of my symptoms?
  • What tests do I need?
  • What treatment do you recommend?
  • How will we know if my treatment is working?
  • Does this condition increase my risk of other medical problems?
  • Does this condition increase my risk of health problems during pregnancy? Are there treatments to reduce that risk?
  • Are there brochures or other printed material I can have? What websites do you recommend?

Don't hesitate to ask other questions, as well.

What to expect from your doctor

Your doctor is likely to ask you a number of questions, including:

  • Do you have a history of strokes or blood clots?
  • Do you have a history of pregnancy complications, such as high blood pressure, miscarriage or stillbirth?
  • Do you have lupus or another autoimmune disorder?
  • Have you ever been tested for sexually transmitted infections or chronic viral diseases, such as hepatitis?
  • Do you have frequent headaches?
  • Have you noticed a red, net-like rash on your wrists or knees?
  • Do you smoke?

Feb 25, 2022

  1. Antiphospholipid antibody syndrome. National Heart, Lung, and Blood Institute. https://www.nhlbi.nih.gov/health-topics/antiphospholipid-antibody-syndrome. Accessed Nov. 9, 2021.
  2. Erkan D, et al. Clinical manifestations of antiphospholipid syndrome. https://www.uptodate.com/contents/search. Accessed Nov. 9, 2021.
  3. Antiphospholipid syndrome. American College of Rheumatology. https://www.rheumatology.org/I-Am-A/Patient-Caregiver/Diseases-Conditions/Antiphospholipid-Syndrome. Accessed Nov. 9, 2021.
  4. AskMayoExpert. Antiphospholipid antibodies and antiphospholipid syndrome. Mayo Clinic; 2021.
  5. Limper M, et al. Antiphospholipid syndrome: State of the art on clinical practice guidelines. Rheumatic and Musculoskeletal Diseases Open. 2018; doi:10.1136/rmdopen-2018-000785.
  6. Sayar Z, et al. Thrombotic antiphospholipid syndrome: A practical guide to diagnosis and management. Thrombosis Research. 2021; doi: org/10.1016/j.thromres.2020.10.010.
  7. Erkan D, et al. Treatment of the antiphospholipid syndrome. https://www.uptodate.com/content/search. Accessed Nov. 9, 2021.
  8. Blood thinner pills: Your guide to using them safely. Agency for Healthcare Research and Quality. http://www.ahrq.gov/patients-consumers/diagnosis-treatment/treatments/btpills/btpills.html. Accessed Nov. 9, 2021.


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