Etripamil

CARDAMYST

Pronunciation: e-TRIP-a-mil (KAR-da-mist)

What it isIntranasal L-type calcium-channel blocker that slows AV-nodal conduction; acute symptomatic paroxysmal SVT.

Why this oneThe first patient-administered therapy designed to terminate an SVT episode without an IV or emergency visit.

What limits itNasal irritation is common; bradycardia, hypotension, and AV block are the key safety concerns.

FDA-approved for

Principal riskSyncope from hypotension

Therapeutic safety burden2 / 4

Overdose danger3 / 4

Weight-gain liability0 / 4

Sedation liability0 / 4

QT / Torsades0 / 4

Direct muscarinic antagonism0 / 4

Embryofetal risk2 / 4

Legacy pregnancy categoryN/A (post-2015 labeling)

Defining liabilityHypotension, syncope and atrioventricular conduction slowing

NO BOXED WARNINGS

FDA dosing	Population	Start	Target	Max
Paroxysmal supraventricular tachycardia (PSVT)	adults	70 mg intranasal (one spray each nostril) at symptom onset	70 mg intranasal PRN	140 mg intranasal / 24 h

Renal Undefined

Hepatic Undefined

Do not exceed 140 mg in 24 h; wait 10 min before repeat dose

Intranasal use only; administer as soon as possible after PSVT symptom onset, one spray into each nostril (70 mg total)
Administer in a sitting position where fall risk is minimal
If symptoms persist after 10 min, give a second 70 mg dose (one spray each nostril)
Seek emergency help if symptoms do not improve within 20 min after the second dose
If a full initial dose is not delivered (device malfunction/misuse), wait at least 10 min before a second dose

Available strengths

Heart failure — NYHA Class II to IV
Wolff-Parkinson-White (WPW), Lown-Ganong-Levine (LGL) syndromes, or manifest pre-excitation (delta wave) on 12-lead ECG
Sick sinus syndrome without a permanent pacemaker
Second degree AV Mobitz 2 block or higher degree of AV block

Syncope/dizziness from hemodynamic effects (BP, HR, cardiac conduction) — administer in a sitting position; monitor patients at risk for hemodynamic instability

Pregnancy No human data; animal (IV) studies showed no clear fetal harm at exposures near/above MRHD

Lactation No data on etripamil in milk; interrupt breastfeeding and pump and discard milk for 12 h after a dose

Etripamil (CARDAMYST)

What pharmacies pay · NADAC 9/30/26

Strength		#/mo	generic $/unit	brand $/unit	CostPlus
70 mg	nasal spray	per unit	—	$790.10/ea	not offered