Drugs Currently Used for Treatment of PAH

Class	Medication	Mechanism	Route	Starting	Maintenance	Half-life	Company	Available
Standard	Digoxin	Inhibits Na+ pump	PO/IV	0.0625–0.25 mg daily	Increase q2 wks for desired effect	36–48 hrs	GSK	Globally
Diuretic	Multiple	Renal-based	PO/IV	Varies	Titrate as needed	Varies	Generic	Globally
Anti-coagulation	Warfarin	Vitamin K antagonist	PO	Varies	Goal INR 2.0	40 hrs	Generic	Globally
Calcium channel blockers	Nifedipine XR	Block VDCC	PO	30mg daily	Titrate to max dose as tolerated	7 hrs	Pfizer	Globally
	Diltiazem XR	Block VDCC	PO/IV	120mg daily	Titrate to max dose as tolerated	5–10 hrs	Generic	Globally
	Amlodipine	Block L-type VDCC	PO	5mg daily	Titrate to max dose as tolerated	30–50 hrs	Generic	Globally
Nitric oxide	NO	Increases cGMP	Inh	Acute test-10–20ppm for 10 min		15–30 sec	INO Therapeutics	Globally
Adenosine	Adenosine	Via receptors A1, A2A, A2B, A3	IV	Acute testing: 50 mg/kg/min	Titrate to symptoms or 350mcg/kg/min	<10 sec	Astellas Pharma US	Globally
Endothelin receptor antagonists (ERAs)	Bosentan	Block both ETA and ETB	PO	62.5mg b.i.d	Increase to 125 mg, b.i.d. after 4 wks	5 hrs	Actelion	Globally
	Ambrisentan	Block ETA only	PO	5mg daily	Consider increase to 10 mg daily	9 hrs	Gilead	Globally
	Sitaxsentan	Blocks ETA>>ETB	PO	100mg daily		10 hrs	Pfizer
PDE inhibitors	Sildenafil	PDE5 Inhibition	PO	20mg 3 times daily		4 hrs	Pfizer	Globally
	Tadalafil	PDE5 Inhibition	PO	40mg daily		17.5 hrs	United Therapeutics	Globally
Prostacyclianalogues	Beraprost	PGI2 analogue	PO	20g, q.i.d.	Increase by 20g, q.i.d., as tolerated	35–40 min	United Therapeutics	Asia
	Iloprost	PGI2 analogue	Inh	2.5mg 6–9 times daily	Increase to 5 mg 6–9 times daily	20–30 min	Actelion	Globally
	Treprostinil	PGI2 analogue	Inh	6 mg, q.i.d.	Up to 18 mg, q.i.d.	4 hrs	Lung Rx, Inc
Iloprost	PGI2 analogue	IV	1–2ng/ kg/min		13 min	Schering Healthcare	not in USA
	Epoprostenol	PGI2 analogue	IV	2ng/kg/min	Increase every 15 min until side effects occur	3–5 min	Actelion	Globally
	Treprostinil	PGI2 analogue	IV	1.25ng/kg/ min	Increase <1.25 ng/ kg/min q wk for 4 wks and after <2.5 ng/kg/ min q wk	4–5 hrs	United Therapeutics	Globally
	Treprostinil	PGI2 analogue	SC	1.25ng/kg/ min	Increase <1.25 ng/ kg/min q wk for 4 wks and after <2.5 ng/kg/ min q wk	4–5 hrs	United Therapeutics	Globally

Abbreviations: PAH: pulmonary arterial hypertension; PO: oral; IV: intravenous; Inh: inhalation; PDE: phosphodiesterase; VDCC: voltage-dependent calcium channels; SC: subcutaneous; b.i.d.: twice a day; q.i.d.: four times a day.