A generic drug is a copy of the brand-name drug with the same dosage, safety, strength, quality, consumption method, performance, and intended use. Before generics become available on the market, the generic company must prove it has the same active ingredients as the brand-name drug and works in the same way and in the same amount of time in the body.
The only differences between generics and their brand-name counterparts is that generics are less expensive and may look slightly different (eg. different shape or color), as trademarks laws prevent a generic from looking exactly like the brand-name drug.
Generics are less expensive because generic manufacturers don't have to invest large sums of money to develop a drug. When the brand-name patent expires, generic companies can manufacture a copy of the brand-name and sell it at a substantial discount.
Letairis prevents thickening of the blood vessels, especially those in the lungs and heart. Ambrisentan also lowers blood pressure in your lungs, helping your heart pump blood more efficiently. Letairis is used to treat pulmonary arterial hypertension (PAH) in adults. It improves your ability to exercise and prevents your condition from getting worse. Letairis is sometimes used with a medicine called tadalafil (Adcirca).
You should not use Letairis if you are allergic to ambrisentan, or if you have idiopathic pulmonary fibrosis (IPF). Do not use Letairis if you are pregnant or think you might be pregnant. This medicine can cause serious birth defects. Tell your doctor right away if you miss a menstrual period or think you may have become pregnant.
Get emergency medical help if you have signs of an allergic reaction to Letairis: severe shortness of breath, wheezing, cough with foamy mucus, chest pain; swelling, tiredness, rapid weight gain; low red blood cells (anemia) - pale skin, unusual tiredness, feeling light-headed or short of breath, cold hands and feet; or liver problems - loss of appetite, stomach pain (upper right side), nausea, vomiting, fever, itching, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes). stuffy nose, sinus pain; or hot flashes, redness in your face.