ambrisentan

Absorption: Extent of absorption following oral administration unknown.

Distribution: Unknown.

Protein Binding: 99%.

Metabolism/Excretion: Highly metabolized.

Half-Life: 15 hr (effective half-life 9 hr).

Time/Action Profile ⬆ ⬇

(plasma concentrations)

ROUTE	ONSET	PEAK	DURATION
PO	unknown	2 hr	24 hr

Contraind./Precautions ⬆ ⬇

Contraindicated in:

OB: Pregnancy;
Lactation: Lactation;
Idiopathic pulmonary fibrosis;
Moderate or severe hepatic impairment;
Significant anemia.

Use Cautiously in:

Mild hepatic impairment;
Rep: Women of reproductive potential;
Pedi: Safety and effectiveness not established in children.

Adv. Reactions/Side Effects ⬆ ⬇

CV: peripheral edema(more common when used with tadalafil)

GU: ↓sperm count

Hemat: ↓hemoglobin

Neuro: headache

Resp: PULMONARY VENO-OCCLUSIVE DISEASE

Interactions ⬆ ⬇

Drug-drug:

Cyclosporine may ↑ levels and risk of toxicity; do not exceed ambrisentan dose of 5 mg once daily.

Route/Dosage ⬆ ⬇

PO (Adults ): 5 mg once daily, may ↑ to 10 mg once daily.

Availability ⬆ ⬇

(Generic available)

Tablets: 5 mg; 10 mg

Assessment ⬆ ⬇

Assess for signs and symptoms of primary pulmonary hypertension (dyspnea, exercise intolerance) prior to and periodically during therapy.
Assess for peripheral edema during therapy. If clinically significant peripheral edema occurs, with or without weight gain, evaluate for underlying cause, such as heart failure, and treat.
Monitor for symptoms of acute pulmonary edema (dyspnea, cough with frothy sputum, anxiety, restlessness, palpitations) during initiation of therapy. Consider the possibility of pulmonary veno-occlusive disease; if confirmed discontinue ambrisentan.

Lab Test Considerations:

Verify negative pregnancy test prior to, monthly during therapy, and 1 mo following completion of therapy.
- Monitor hemoglobin prior to and at 1 mo and periodically during therapy. May cause ↓ hemoglobin; usually occurs during first few wk and stabilizes. If clinically significant and other causes have been excluded, discontinue therapy.

Implementation ⬆ ⬇

Do not confuse ambrisentan with Ambien.
Only available through a special restricted distribution program called Ambrisentan REMS due to risks of birth defects. Female patients must be enrolled in Ambrisentan REMS and re-enrolled yearly. A limited number of pharmacies are certified to dispense ambrisentan. Provide patients with telephone number (1-888-417-3172) and website ( www.ambrisentanrems.us.com) for information on how to obtain medication.
PO: May be administered without regard to food. DNC: Tablets should be swallowed whole; do not crush, break or chew.

Patient/Family Teaching ⬆ ⬇

Instruct patient to take ambrisentan as directed, at the same time each day. Review medication guide and patient education brochures with every patient. Explain Ambrisentan REMS to patient. Take missed dose as soon as remembered that day. Take next dose at regular time; do not take two doses at the same time to make up for missed dose.
Advise patient to notify health care professional promptly if symptoms of fluid retention (swelling of hands, legs, ankles, feet or all over the body) or hepatotoxicity (anorexia, nausea, vomiting, fever, malaise, fatigue, right upper quadrant abdominal discomfort, jaundice, dark urine or itching) occur.
Rep: May cause fetal harm if taken during pregnancy. Inform patients a pregnancy test is required prior to beginning therapy and acceptable methods of contraception (one highly effective form of contraception: intrauterine devices [IUD], contraceptive implants, or tubal sterilization or a combination of methods: [hormone method with a barrier method or two barrier methods]) must be used throughout therapy and for 1 mo following discontinuation. If a partner’s vasectomy is method of contraception chosen, a hormone or barrier method must be used along with this method. Educate women with reproductive potential on the use of emergency contraception in the case of unprotected sex or contraceptive failure. Advise patient to avoid breastfeeding during therapy. Advise patient to notify health care professional if pregnancy is suspected.
Rep: Inform patients that ambrisentan may cause low sperm count.
Advise patient of the importance of regular liver and hemoglobin testing.

section name header

Pronunciation ⬇

Classifications ⬆ ⬇

Indications ⬆ ⬇

Action ⬆ ⬇

Pharmacokinetics ⬆ ⬇