Pulmonary Arterial Hypertension Pregnancy: There are no or limited data from use in pregnant women; animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity. Given the absence of alternative medicinal products, epoprostenol can be used in women who choose to continue their pregnancy despite the known risk of pulmonary arterial hypertension in pregnancy. It is unknown whether epoprostenol or its metabolites are excreted in human milk and a risk to the newborn/infant cannot be excluded — breast-feeding should be discontinued during treatment.

Epoprostenol

Brand names: Flolan, Veletri

Epoprostenol is a prostacyclin (PGI2) analogue given by continuous intravenous infusion, used in the management of pulmonary arterial hypertension and as an inhaled selective pulmonary vasodilator in critical care.

Adult dose

Dose: Pulmonary arterial hypertension — short-term (acute) dose ranging: start the infusion at 2 nanograms/kg/min and increase by increments of 2 nanograms/kg/min every 15 minutes or longer until maximum haemodynamic benefit or dose-limiting pharmacological effects are elicited (if 2 nanograms/kg/min is not tolerated, identify a lower tolerated dose). Long-term continuous infusion: start at 4 nanograms/kg/min LESS than the maximum tolerated infusion rate determined during short-term dose ranging; if the maximum tolerated rate is 5 nanograms/kg/min or less, start the long-term infusion at 1 nanogram/kg/min.

Route: Continuous intravenous infusion only. Short-term dose ranging may be given via a peripheral or central venous line (peripheral use restricted to short duration and low concentrations because of the high pH); long-term continuous infusion must be given through a central venous catheter using an ambulatory infusion pump. Must not be administered as a bolus injection.

Frequency: Continuous infusion

Short-term dose ranging must be conducted in a hospital with adequate resuscitation equipment; treatment should only be initiated and monitored by a physician experienced in the treatment of pulmonary arterial hypertension. Dose adjustment: increase the infusion rate in 1 to 2 nanograms/kg/min increments at intervals sufficient to assess clinical response, at least 15 minutes apart; after each new rate, observe the patient and monitor erect and supine blood pressure and heart rate for several hours. The need for increases from the initial long-term dose should be expected over time. Decreases should be made gradually in 2 nanograms/kg/min decrements every 15 minutes or longer until dose-limiting effects resolve. Abrupt withdrawal or sudden large reductions in infusion rate must be avoided because of the risk of a potentially fatal rebound effect; except in life-threatening situations (e.g. unconsciousness, collapse) infusion rates should be adjusted only under the direction of a physician. SEPARATE RENAL DIALYSIS INDICATION (adults): prior to dialysis 4 nanograms/kg/min intravenously for 15 minutes; during dialysis 4 nanograms/kg/min into the arterial inlet of the dialyser; stop the infusion at the end of dialysis — the recommended dose for renal dialysis should be exceeded only with careful monitoring of blood pressure. Elderly: no specific information in patients over 65 years for either indication; select the dose carefully reflecting greater frequency of decreased hepatic, renal or cardiac function and concomitant disease or therapy. Paediatric: safety and efficacy in children younger than 18 years have not yet been established. Only extension sets with an in-line 0.22 micron filter (preferably a hydrophilic polyethersulfone membrane) may be used between the pump and the central venous catheter, and the extension set and filter must be changed at least every 48 hours. Reconstituted solutions must be further diluted to the final concentration within one hour of reconstitution and must not be used if discoloured or containing particles. Section 4.5 was not fetched from the SPC; the interactions listed below are taken from section 7 of the US epoprostenol injection label in this bundle (Mylan Institutional LLC) — same active substance and route — and should be confirmed against the UK SPC.

Dose independently re-sourced from UK Summary of Product Characteristics (SPC) via the eMC; US FDA prescribing information (openFDA / DailyMed) — cross-check; US labelling may differ from UK — clinician-reviewed. Always confirm against the product SmPC and your local formulary before prescribing.

Contraindications

Hypersensitivity to the active substance or to any of the excipients
Congestive heart failure arising from severe left ventricular dysfunction
Must not be used chronically in patients who develop pulmonary oedema during dose-ranging

Side effects

Headache (very common)
Facial flushing (very common; seen even in the anaesthetised patient)
Nausea, vomiting and diarrhoea (very common)
Jaw pain (very common) and unspecified pain (very common)
Hypotension (common); tachycardia at doses of 5 nanograms/kg/min and below and bradycardia at doses above 5 nanograms/kg/min
Sepsis/septicaemia mostly related to the delivery system, and bleeding at various sites with decreased platelet count (common)

Interactions

Diuretics, antihypertensive agents or other vasodilators — additional reductions in blood pressure may occur (US label section 7)
Antiplatelet agents or anticoagulants — potential for epoprostenol to increase the risk of bleeding (US label section 7); the SPC also notes epoprostenol is a potent inhibitor of platelet aggregation and an increased risk of haemorrhagic complications should be considered
Digoxin — patients may show elevations of digoxin concentrations after initiation of epoprostenol, which may be clinically significant in patients prone to digoxin toxicity (US label section 7)
Drugs which affect cardiovascular reflexes may mask the effects of epoprostenol on heart rate (SPC section 4.4)

Clinical monograph

How it works

It is a potent vasodilator of pulmonary and systemic arterial beds and inhibits platelet aggregation by stimulating prostacyclin receptors and increasing intracellular cyclic AMP.

Prescribing in practice

Abrupt interruption of the continuous infusion can precipitate life-threatening rebound pulmonary hypertension, so a backup delivery system and uninterrupted dosing are essential.
It has a very short half-life and is unstable, requiring reconstitution with the specific buffer and delivery through a dedicated indwelling central line.
Systemic effects include hypotension, flushing, jaw pain and headache, and it potentiates the effect of other antihypertensives and anticoagulants.

Monitoring

Monitor blood pressure, heart rate and signs of infusion-related effects continuously during initiation and dose titration, with central line care to detect catheter-related sepsis.

Counselling the patient

Never stop or pause the pump without medical advice as symptoms can return suddenly and severely.
Report fever, line-site redness, dizziness or fainting promptly.
Carry spare pump consumables and know how to manage an infusion failure.

Evidence & guidelines

Long-established as a first-line parenteral therapy for advanced pulmonary arterial hypertension and supported by UK pulmonary hypertension specialist guidance.

Reference: ESC/ERS PAH Guidelines 2022; NICE TA459; MHRA SPC Flolan/Veletri; Lancet 1996; 347(9000):322-328 (first RCT); Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. The structured dose values shown have been reviewed by a clinician. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

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