Ambrisentan, also known by its brand name Letairis, is a medication used for pulmonary arterial hypertension (PAH), or high blood pressure in the blood vessels of the lungs. This medication is available as a lower-cost generic. The usual dose is one tablet daily. Ambrisentan (Letairis) is generally well-tolerated, though the most common side effect is swelling in the arms or legs. It also has a risk of causing severe and life-threatening harm to unborn babies, so the medication is only available through the Ambrisentan REMS program for people who can get pregnant.
Pulmonary arterial hypertension (PAH)
Ambrisentan (Letairis) is an endothelin receptor antagonist. It works by blocking the effects of a protein called endothelin. Doing so relaxes the blood vessels that go from your heart to your lungs and allows more blood to flow through. This lowers the amount of work your heart needs to pump blood to your lungs to get oxygen for your body. As a result, it's easier for you to exercise and breathe.
Source:Â DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
More common
Bloating or swelling of the face, arms, hands, lower legs, or feet
rapid weight gain
tingling of the hands or feet
unusual weight gain or loss
Less common
fast, irregular, pounding, or racing heartbeat or pulse
headache
muscle aches
pain or tenderness around the eyes and cheekbones
stuffy or runny nose
tightness of the chest
trouble breathing
unusual tiredness or weakness
Incidence not known
clay colored stools
dark urine
decrease in the amount of urine
decreased appetite
dilated neck veins
extreme tiredness or weakness
irregular breathing
large, hive-like swelling on the face, eyelids, lips, tongue, throat, hands, legs, feet, or genitals
loss of appetite
noisy, rattling breathing
pale skin
skin rash, itching
stomach pain or tenderness
troubled breathing at rest
troubled breathing with exertion
vomiting
yellow skin or eyes
Get emergency help immediately if any of the following symptoms of overdose occur:
Symptoms of overdose
Blurred vision
confusion
dizziness, faintness, or lightheadedness when getting up suddenly from a lying or sitting position
sweating
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Less common
Difficulty having a bowel movement
feeling of warmth
redness of the face, neck, arms, and occasionally, upper chest
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Works well to slow the worsening of PAH and improve ability to breathe and exercise
Taken once a day with or without food
Generally mild or moderate side effects
Only available through a REMS program so that it's safe for people who can become pregnant
Not a cure for PAH
Might affect sperm count and ability to have children in males
Females who can have children must use birth control and take a pregnancy test every month
Not for people with a lung problem called idiopathic pulmonary fibrosis (IPF) because of risk of harm
Make sure to mark your appointments on your calendar to see your provider or get any bloodwork done (e.g., liver tests, blood cell counts, pregnancy test for females, etc.). These appointments are important for making sure ambrisentan (Letairis) is working well and is as safe for you as possible.
You can take ambrisentan (Letairis) with or without food. But if it's hurting your stomach, taking it with food can help.
Swallow ambrisentan (Letairis) whole. Don't break, crush, or chew the tablet. Let your provider know if you can't swallow the tablets.
Tell your provider if you're taking cyclosporine (Sandimmune, Neoral). These medications can make the levels of ambrisentan (Letairis) in your body get too high. Your ambrisentan (Letairis) dose might need to be adjusted to keep you safe.
If you're able to get pregnant, it's recommended that you use two forms of birth control during treatment with ambrisentan (Letairis) and for at least 1 month after your last dose. You'll also need to take a pregnancy test every month during treatment and 1 month after your last dose. It's important to avoid getting pregnant because the medication can harm an unborn baby. Tell your provider right away if you get pregnant while you're taking ambrisentan (Letairis).
If you're a male and are prescribed ambrisentan (Letairis), let your provider know if there's a possibility you might want to have children in the future. This medication might not be the best option for you because ambrisentan (Letairis) can potentially lower your sperm count. It's not known if this effect is reversible after you stop the medication.
Don't stop taking ambrisentan (Letairis) unless your provider tells you to, even if you start to feel better. Stopping ambrisentan (Letairis) can cause your symptoms to come back and can worsen your PAH.
Ambrisentan (Letairis) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Ambrisentan (Letairis) shouldn't be taken during pregnancy because it can cause severe and life-threatening harm to unborn babies. Because of this risk, ambrisentan (Letairis) is available only through the Ambrisentan REMS program for females who can get pregnant. This Risk Evaluation and Mitigation Strategies (REMS) program helps make sure that the medication is as safe as possible for them.
If you're able to get pregnant, your provider will ask you take a pregnancy test before you start ambrisentan (Letairis), monthly during treatment, and once more a month after you stop the medication. You should use two forms of birth control during treatment with ambrisentan (Letairis) and for at least 1 month after completing treatment. Contact your provider right away if you become pregnant while taking ambrisentan (Letairis).
Risk factors: Heart failure
Ambrisentan (Letairis) can cause fluid buildup in the body, leading to swelling or shortness of breath. Fluid buildup can start to happen within weeks of starting ambrisentan (Letairis). If you have a history of heart failure, this fluid buildup can be severe and worsen your heart condition. Let your provider know before starting ambrisentan (Letairis) if you have any heart problems or heart failure. Contact your provider if you have any signs of heart failure, like shortness of breath; swelling in the legs, ankles, or feet; irregular heartbeat; not able to exercise; or tiredness, while you're taking ambrisentan (Letairis).
Risk factors: Severe anemia
Ambrisentan (Letairis) might cause your hemoglobin levels to go down. In studies, a drop in hemoglobin levels happened within the first few weeks of starting ambrisentan (Letairis), but then stabilized throughout treatment. Hemoglobin is the protein on your red blood cells that carries oxygen to the rest of your body. Low hemoglobin levels can lead to anemia (low red blood cell count).
You'll need regular blood tests while you're taking ambrisentan (Letairis) so your provider can check your hemoglobin levels during treatment. If you have a history of anemia, speak with your provider before taking ambrisentan (Letairis) so they can make sure it's safe for you. Let your provider know if you experience symptoms of anemia, such as weakness, shortness of breath, dizziness, fast or irregular heartbeat, or pale skin, while you're taking ambrisentan (Letairis).
The typical starting dose is 5 mg by mouth once per day. After 4 weeks, your provider might raise your dose if needed. The maximum recommended dose is 10 mg per day.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Currently pregnant
Lung condition called idiopathic pulmonary fibrosis (IPF)
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