Yaz Side Effects

The Yaz birth-control pill has been linked to an increased risk for blood clots that can travel to the lungs, heart and brain and lead to serious medical conditions, including death. The drug is also linked to gallbladder disease, high cholesterol and high potassium levels that can lead to heart attacks.

With its chic marketing and catchy name, the Yaz birth control pill was introduced in 2006 and quickly became the most popular and best-selling oral contraceptive in the U.S. But as quickly as the drug’s popularity skyrocketed, it plummeted amid concerns that it raises the risks of deadly side effects more than older contraceptive pills.

Studies from as early as 2006 documented the side effects associated with Yaz, including:
  • Thromboembolic disorders
  • Hyperkalemia
  • Breast cancer
  • Reproductive organ cancer
  • Liver disease
  • High blood pressure
  • Gallbladder disease

Some side effects, such as irregular bleeding, nausea, breast tenderness and headache, are usually mild and tend to disappear with time. Others, such as blood clots, stroke, heart attack and gallbladder disease, are more serious and can lead to death.

Yaz Increases Blood-Clot Risks

Microscopic view of a blood clot, which can be caused by Yaz

Studies show that drospirenone, an active ingredient in Yaz, significantly increases the chances of developing venous thromboembolic events (VTE), or blood clots. The risk of developing a blood clot while taking Yaz goes up even more in women who smoke and are 35 and older. Blood clots can lead to heart attacks, strokes and pulmonary embolisms, all of which can be deadly.

At least five large studies conducted since 2009 have shown that drospirenone not only heightens the risk of blood clots but it does so more than older forms of progesterone. A study by the U.S. Food and Drug Administration (FDA), for example, showed a 74 percent increased risk in Yaz users when compared to users of other oral contraceptives. Bayer, the maker of Yaz, funded the only two major studies that disprove the blood-clot connection. In 2012, the FDA decided to include an updated warning on the drug’s label.

Blood Clot Symptoms

The signs and symptoms of blood clots can vary depending upon where the clot is located (whether in a vein or an artery) and its size. This can also affect the severity of the symptoms. For example, if the clot is lodged in an artery that feeds into the brain (stroke), then confusion and/or paralysis may be apparent.

Alternatively, a clot in an artery leading to the heart can cause a heart attack. And in instances of deep vein thrombosis (DVT), or a clot in a deep vein within the body (such as the leg), a patient may be unable to walk well, or may suffer pain or tingling in the leg below the clot.

As a result, the following problems may be caused:
Chest heaviness or pain, discomfort in other areas of the upper body, shortness of breath, sweating, nausea, lightheadedness.
Weakness of the face, arms or legs, difficulty speaking, vision problems, sudden and severe headache, dizziness.
Arm or Leg
Sudden or gradual pain, swelling, tenderness and warmth.
Sharp chest pain, racing heart, shortness of breath, sweating, fever, coughing up blood.
Severe abdominal pain, vomiting, diarrhea.

Treatment for Blood Clots

Treatment for a blood clot varies depending on the size and location of the clot. Blood clots require immediate medical attention. Certain medicines called anticoagulants, or blood thinners, can prevent blood clots from forming, while another group of medications called thrombolytics, help to dissolve clots that have already formed.

In a procedure referred to as a directed thrombolysis, a catheter —a thin, flexible tube — is inserted into the patient’s body, delivering a clot-dissolving drug directly to the blockage.

Sometimes a surgical procedure called a thrombectomy is required for clot removal. This is especially true in situations where the blood clot is large or positioned in a particularly risky location within the patient’s body.

Deep Vein Thrombosis (DVT)

Deep Vein Thrombosis Impedes Blood Flow
DVT is a clot that forms in the body’s deep veins

Specifically, Yaz is linked to deep vein thrombosis (DVT), a blood clot that develops in the deep veins of the body, according to a 2011 study in the British Medical Journal (BMJ). Evaluating 1.3 million Danish and Dutch women, the study found a six-fold increased risk of blood clots in women using drospirenone compared to women not taking the pill, according to The New York Times.

Known as the long-haul traveler’s condition, DVT typically forms in the legs, often after long periods of inactivity. It is usually seen in older patients who are sedentary or have heart failure. When the clot forms in the deep veins of the legs, it is often painful and causes the legs to swell. Sometimes there are no symptoms.

Once a DVT forms, the clot can easily break off and travel through the body and create numerous dangers, including:
If a blood clot travels to the brain, the clot can cut off blood flow and cause a rapid loss of brain functions. The resulting effects could include paralysis and death.
Pulmonary embolism
A clot that gets lodged in the narrow arteries in the lungs is called a pulmonary embolism. This type of clot makes it difficult for the lungs to provide the necessary oxygen to the rest of the body.
Heart attack
Also called coronary thrombosis, a blood clot in the heart can cause the heart muscle to stop. Yaz tends to increase potassium levels, which also raises the risk of heart attack.

Seemingly healthy females, some as young as 14 and 15, have reportedly died from Yaz-related DVT. Countless others have allegedly been injured. Bayer refutes the claims. It says the risks of taking Yaz are no different than any other oral contraceptive.

However, in 2015, a study published in BMJ looked at nearly 11,000 cases of blood clots in women aged 15 to 49, and found the risks of blood clots associated with birth-control pills to be higher for newer oral contraceptives like Yaz compared to older drugs.

Dangerous Symptoms

According to the National Institutes of Health (NIH), most deep-vein blood clots occur in the lower leg or thigh, but they can also occur in other parts of the body, such as the arms and pelvis. Blood clots in the thighs are more likely to break off and cause another dangerous health condition called pulmonary embolism (or PE), than clots that form in the lower legs or other deep veins located throughout the body.

If the vein affected by the blood clot swells, the condition is known as thrombophlebitis. Symptoms of thrombophlebitis are similar to the signs related to deep vein thrombosis (DVT) in general.

The symptoms of thrombophlebitis can include:
  • Changes in skin color (redness)
  • Leg pain, or pain in the part of the body affected
  • Leg swelling (edema), or swelling in the part of the body affected
  • Skin that feels warm to the touch
  • Tenderness over the affected vein (especially in cases of thrombophlebitis)

Treatment for Deep Vein Thrombosis (DVT)

Medicines to ease pain and inflammation, break up existing blood clots and prevent new clots from forming are all used as treatment options for deep vein thrombosis (DVT). Elevating the affected area and applying moist heat can also assist in healing. Taking breaks from sitting to walk and stretch the legs and drinking plenty of fluids can not only help patients suffering from existing DVT, but it can also help those at risk from developing DVT.

Blood thinners, or anticoagulants, such as heparin or warfarin (Coumadin), as well as some of the new generation blood thinners, such as Xarelto, Pradaxa, Eliquis and Savasaya, may be prescribed to prevent new clots from forming, especially when deep veins are affected by blood clots.


Ischemic Stroke Occur in the Thrombus

Introduced in the 1960s, birth-control pills have long been linked to ischemic strokes, which happen when the blood supply to the brain becomes blocked. Researchers found that the fluctuating estrogen levels in early generations of birth-control pills elevate the risk of blood clots, which can lead to stroke. An increasing number of studies now show that Yaz puts women at an even higher risk of having a stroke than first thought because the risk of DVT is significantly higher with Yaz users.

After developing in the deep body veins, blood clots can break off and travel to the brain. When a blood clot fractures from its original location and ends up near the brain, the clot can limit or cut off blood flow to the brain. When this happens, a stroke is imminent. The resulting stroke can leave patients in a vegetative state or dead. Bayer claims there is no evidence of increased risk.

Treatment for Ischemic Stroke

When having a stroke, or suspecting the occurrence of a stroke, it is important to seek treatment as quickly as possible. Certain blood thinners can be given to a patient as the stroke is happening to stop the stroke by quickly dissolving the blood clot. But according to the National Institutes of Health (NIH), to be most effective, this treatment must be administered within three to four and a half hours after the onset of symptoms. The sooner it’s given, the better the outcome.

Pulmonary Embolism

Pulmonary Artery Blocked by an Embolus
A pulmonary embolism is a blood clot that forms in the lungs

Caused by DVT, a pulmonary embolism is a blood clot that settles in the lungs. Typically, these blood clots in the lungs block a coronary artery, which can lead to heart attack, among other serious medical conditions.

When a blood clot travels to the lungs and blocks the pulmonary arteries, the circulation and blood oxygen levels are restricted. This makes it difficult for the lungs to provide oxygen to the body. The results can be debilitating or deadly.

Sudden Blockage in Artery

Pulmonary embolism (PE) is the result of a sudden blockage in an artery located in the lung. This blockage is most commonly caused by a deep vein blood clot in the vein that has broken free and made its way to the lung. This deep vein clot, characterized as the condition deep vein thrombosis (DVT), usually originates in the leg (especially the thigh) before traveling to the lung.

PE & DVT Link
Signs and symptoms of PE can sometimes mimic, or are related to, those present in DVT, according to the National Institutes of Health (NIH).

These can include swelling of the leg or along a vein in the leg affected by the clot, pain or tenderness in the leg, a feeling of increased warmth in the area of the leg that’s swollen or tender, and red or discolored skin on the affected leg.

Treatment for Pulmonary Embolism (PE)

The National Institutes of Health (NIH) estimates that pulmonary embolisms (PE) affects about 300,000 to 600,000 people in the U.S. every year. If left untreated, about 30 percent of those individuals will die, with most dying within the first few hours of the clotting occurrence.
Therefore, a PE requires immediate emergency medical treatment. A patient may receive medications to prevent more clots as well as to dissolve the existing clot, called thrombolytic therapy. If a patient is unable to take blood thinners, surgery may be necessary to place a device called an inferior vena cava filter (IVC filter) in the main vein located in the belly to keep large clots from traveling to the lungs. This can be a temporary fix that can be removed later.

PE is a serious condition that can cause long-term or permanent damage. Some patients can develop long-term heart and lung problems.

Health complications resulting from PE include:
  • Damage to part of the lung because of lack of blood flow to the lung tissue (can lead to pulmonary hypertension, or increased blood pressure in the arteries of the lung)
  • Low oxygen levels in the blood
  • Damage to other organs in the body due to lack of oxygen

Heart Attack

Elevated Potassium Buildup in Heart

Not only does Yaz’ blood clotting risk increase the chances of a heart attack, but so does the drug’s link to dangerously high potassium levels, called hyperkalemia. Potassium is an important mineral for proper cell functioning and is crucial to heart functioning. It plays a key role in smooth muscle contractions.

Drospirenone found in Yaz affects potassium levels by interfering with the normal functioning of the kidney, which monitors and regulates the body’s potassium levels. When the kidney function is stalled, potassium builds in the bloodstream.

When blood contains too much potassium, it can cause these problems:
  • Irregular heart beat
  • Cardiac arrest
  • Changes in muscle control
  • Paralysis
  • Muscle weakness and fatigue

Some drugs, such as ibuprofen, high-blood pressure medicine and certain diuretics, can have serious interactions with Yaz and cause hyperkalemia. Yaz should not be taken if you have kidney failure, one kidney, liver disease, adrenal disease or a history of blood clots. Some everyday tasks, such as drinking sports drinks or eating high-potassium foods, coupled with taking Yaz can be dangerous for women. The risk from a potassium-induced heart attack is so great that federal drug regulators demanded that Bayer include the information on the drug packaging and labeling.

What to Watch Out For

The symptoms of abnormally high levels of potassium are fairly nonspecific, if a patient suffers from any symptoms at all, and can include muscle weakness, nausea, malaise (general ill feeling), heart palpitations, or a slow, weak or irregular pulse. When the heartbeat gets too slow, or even stops, the patient may suddenly collapse.

Treatment for Heart Attack/Elevated Potassium Levels

If a patient’s potassium level is very high, or if they are exhibiting any warning signs of the condition, such as changes in an electrocardiogram (ECG) (a test that records the electrical activity of the heart), then emergency treatment is necessary. Emergency treatment measures might include calcium administered by IV to treat the muscle and heart effects of high potassium levels, glucose and insulin given by IV to lower the potassium levels, kidney dialysis, and certain medicines to help remove potassium from the intestines so it cannot be absorbed.

Emergency procedures, such as an angioplasty (a medical procedure to open narrowed or blocked blood vessels that supply blood flow to the heart), is often the first choice of treatment. A stent (a small, metal mesh tube that opens up inside a heart artery) may be placed during or after an angioplasty to prevent the artery from closing again. Certain medications may also be prescribed to break up clots.

More invasive surgery, called heart bypass surgery, is sometimes necessary to open narrowed or blocked blood vessels in or supplying the heart.

Gallbladder Disease

Yaz has also been proven to increase the chances of gallbladder disease and surgical removal of the gallbladder, called cholecystectomy. A study published in the Canadian Medical Association Journal (CMAJ) concluded that drospirenone found in Yaz increased a woman’s risk for developing gallbladder problems by 20 percent. The study called it a “small, statistically significant increase in the risk of gallbladder disease.”

A CMAJ study found that the drospirenone found in Yaz increased the risk for developing gallbladder problems by 20 percent.

Some studies say drospirenone is linked to gallbladder disease because of its diuretic effect. Other studies say the link between Yaz and gallbladder disease is because the drug increases cholesterol levels, thus creating calcified bits of cholesterol in the gallbladder, known as gallstones. Still others say it is because drospirenone decreases the gallbladder’s movement and impedes bile flow.

Bayer refutes all the research pointing to gallbladder problems, saying that it is not clinically significant.

Yaz Increases Cholesterol Bile

According to Medical News Today, “Most people don’t pay much attention to their gallbladder until it starts causing trouble.” The organ’s primary function is to store and concentrate bile, a digestive liquid. Yaz increases cholesterol levels in bile and decreases gallbladder movement. This could lead to the formation of calcified cholesterol chunks known as gallstones, and the gallbladder could become inflamed.

Please seek the advice of a medical professional before making health care decisions.

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Kristin Compton
Written By Kristin Compton Writer

Kristin Compton's background is in legal studies. She worked as a paralegal before joining Drugwatch as a writer and researcher. She was also a member of the National Association of Legal Assistants. A mother and longtime patient, she has firsthand experience of the harmful effects prescription drugs can have on women and their children. Some of her qualifications include:

  • Bachelor of Arts in Legal Studies | Pre-Law from University of West Florida
  • Past employment with The Health Law Firm and Kerrigan, Estess, Rankin, McLeod & Thompson LLC
  • Personal experience battling severe food allergies, asthma and high-risk pregnancies
Edited By
Kevin Connolly
Kevin Connolly Managing Editor

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