Sudden arrhythmic death syndrome


Drugs to avoid

Anyone with a condition affecting the heart that can cause sudden cardiac death needs to take extra care with medicines. All medicines – both those prescribed by your doctor and any you buy over the counter – must be checked, as some can increase the risk of sudden death.

For people with LQTS there are specific medications that can have a serious effect by further prolonging the QT interval. We give a list of these medicines below. This list includes drugs that can stimulate and irritate the heart by causing adrenaline-like effects. You must always check with your GP or cardiologist before taking any new medication, as this list will change with time.

In people with Brugada Syndrome the number and range of drugs that may make the condition worse is unknown and caution must be used. Antiarrhythmics, beta-blockers and some antidepressants are known to interact badly with it.

Drugs which people with Long QT Syndrome should avoid

Below is a list of the drugs that people with Long QT Syndrome should avoid.  A similar list can also be found by clicking here.

Neither of these lists should be considered exhaustive, and you should always check with your GP and pharmacist if your doctor prescribes any new drugs for you, as these lists may not be complete.

* = Drugs which are unlicensed, withdrawn or suspended in the UK market

A – Z List

  Aclarubicin   Anti-cancer
  Adrenaline (Epinephrine)   Stimulant
  Ajmaline*   Antiarrhythmic (Class 1)
  Alfuzosin   Alpha1-blocker
  Almokalant*   Antiarrhythmic (Class 3)
  Amantidine   Antimalarial
  Amiodarone   Antiarrhythmic (Class 3)
  Amitriptyline   Psychiatric drug – Tricyclic antidepressant
  Amoxapine*   Psychiatric drug – Tricyclic antidepressant
  Amphetamine   Stimulant
  Amsacrine   Anti-cancer
  Arsenic trioxide   Anti-cancer
  Astemizole*   Antihistamine
  Atomoxetine   Psychiatric drug – Other
  Azelastine   Antihistamine
  Azimilide*   Antiarrhythmic (Class 3)
  Azithromycin   Antibiotic – Macrolide
  Bepridil*   Anti-anginal / vasodilator
  Bretylium   Antiarrhythmic (Class 3)
  Chloral hydrate   Sedative
  Chloroquine   Antimalarial
  Chlorpromazine   Psychiatric drug – Phenothiazine
  Cibenzoline*   Antiarrhythmic (Class 1)
  Cimetidine   Histamine H₂ receptor antagonist
  Ciprofloxacin   Antibiotic – Quinolone
  Cisapride*   Serotonin agonist / antagonist
  Citalopram   Psychiatric drug – Other
  Clarithromycin   Antibiotic – Macrolide
  Clobutinol*   Other
  Clomipramine   Psychiatric drug – Tricyclic antidepressant
  Clozapine   Anti-psychotic
  Cocaine   Stimulant
  Cold remedies   May contain stimulant drugs – always to check the label
  Cotrimoxazole   Antibiotic – Antifungal
  d-sotalol*   Antiarrhythmic (Class 3)
  Desipramine*   Psychiatric drug – Tricyclic antidepressant
  Dexmethylphenidate   Stimulant
  Dihydroquinidine*   Antiarrhythmic (Class 1)
  Diphenhydramine   Antihistamine
  Disopyramide   Antiarrhythmic (Class 1)
  Dobutamine   Stimulant
  Dofetilide*   Antiarrhythmic (Class 3)
  Dolasetron   Serotonin agonist / antagonist
  Domperidone   Other
  Dopamine   Stimulant
  Doxepin   Psychiatric drug – Tricyclic antidepressant
  Dronedarone*   Antiarrhythmic (Class 3)
  Droperidol*   Psychiatric drug – Other
  Ebastine*   Antihistamine
  Encainide*   Antiarrhythmic (Class 1)
  Ephedrine   Stimulant
  Ersentilide*   Antiarrhythmic (Class 3)
  Erythromycin   Antibiotic – Macrolide
  Felbamate*   Anticonvulsant
  Fenfluramine   Stimulant
  Flecainide   Antiarrhythmic (Class 1)
  Fluconazole   Antibiotic – Antifungal
  Fluoxetine   Psychiatric drug – Other
  Fluphenazine   Psychiatric drug – Phenothiazine
  Foscarnet (HIV)   Antibiotics – Antiviral
  Fosphenytoin (prodrug of Phenytoin)   Anticonvulsant
  Galantamine   Inhibitor (dementia, Alzheimer’s)
  Gatifloxacin*   Antibiotic – Quinolone
  Geldanamycin*   Anti-cancer
  Gemifloxacin*   Antibiotic – Quinolone
  Granisetron   Serotonin agonist / antagonist
  Grepafloxacin*   Antibiotic – Quinolone
  Halofantrine*   Antimalarial
  Haloperidol   Psychiatric drug – Other
  Hydroxyzine   Antihistamine
  Ibutilide*   Antiarrhythmic (Class 3)
  Imipramine   Psychiatric drug – Tricyclic antidepressant
  Indapamide   Anti-hypertensive
  Isoprenaline (Isoproterenol)   Stimulant
  Isradipine   Anti-hypertensive
  Itraconazole   Antibiotic – Antifungal
  Ketanserin*   Serotonin agonist / antagonist
  Ketoconazole   Antibiotic – Antifungal
  Levalbuterol   Stimulant
  Levofloxacin   Antibiotic – Quinolone
  Levomethadyl*   Psychiatric drug – Other
  Lidoflazine*   Anti-anginal / vasodilator
  Lithium   Anti-mania
  Maprotiline   Psychiatric drug – Other
  Memantine   Alzheimers drug
  Mesoridazine   Psychiatric drug – Other
  Metaproterenol   Stimulant
  Methadone   Psychiatric drug – Other
  Methylphenidate   Stimulant
  Mexiletine   Antiarrhythmic (Class 1)
  Midodrine   Stimulant
  Moexipril / Hydrochlorthiazide   Anti-hypertensive
  Moxifloxacin   Antibiotic – Quinolone
  Naratriptan   Anti-migraine
  Nicardipine   Anti-hypertensive
  Nifekalant*   Antiarrhythmic (Class 3)
  Norepinephrine (Noradrenaline)   Stimulant
  Nortriptyline   Psychiatric drug – Tricyclic antidepressant
  Octreotide   Other
  Ofloxacin   Antibiotic – Quinolone
  Ondansetron   Serotonin agonist / antagonist
  Organophosphates*   Other
  Paroxetine   Anti-depressant
  Pentamidine   Antibiotic – Other
  Perflutren lipid microspheres   Other
  Pericycline   Psychiatric drug – Other
  Phentermine   Stimulant
  Phenylephrine   Stimulant
  Phenylpropanolamine   Stimulant
  Pimozide   Psychiatric drug – Other
  Pirmenol*   Antiarrhythmic (Class 1)
  Prenylamine*   Anti-anginal / vasodilator
  Probucol   Other
  Procainamide   Antiarrhythmic (Class 1)
  Prochlorperazine   Psychiatric drug – Phenothiazine
  Propafenone   Antiarrhythmic (Class 1)
  Protriptyline*   Psychiatric drug – Tricyclic antidepressant
  Pseudoephidrine   Stimulant
  Quetiapine   Psychiatric drug – Other
  Quinidine*   Antiarrhythmic (Class 1)
  Quinine   Antimalarial
  Ranolazine   Anti-anginal / vasodilator
  Risperidone   Psychiatric drug – Other
  Ritodrine   Stimulant
  Roxithromycin*   Antibiotic – Macrolide
  Salbutamol (Albuterol)   Stimulant
  Salmeterol   Stimulant
  Sematilide*   Antiarrhythmic (Class 3)
  Sertindole   Psychiatric drug – Other
  Sertraline   Anti-depressant
  Sibutramine   Stimulant
  Solifenacin   Other
  Sotalol   Antiarrhythmic (Class 3)
  Sparfloxacin*   Antibiotic – Quinolone
  Spiramycin   Antibiotic – Macrolide
  Sumatriptan   Anti-migraine
  Sunitib   Anti-cancer
  Tacrolimus   Anti-cancer
  Tamoxifen   Anti-cancer
  Telithromycin   Antibiotic – Macrolide
  Terbutaline   Stimulant
  Terfenadine*   Antihistamine
  Terikalant*   Antiarrhythmic (Class 3)
  Terodiline*   Anti-anginal / vasodilator
  Thioridazine*   Psychiatric drug – Phenothiazine
  Tizanidine   Other
  Tolterodine   Bladder antispasmodic
  Trazodone   Psychiatric drug – Other
  Trifluoperazine   Psychiatric drug – Phenothiazine
  Trimethoprim sulfa (bactrim)   Antibiotic – Other
  Trimipramine   Psychiatric drug – Tricyclic antidepressant
  Vardenafil   Anti-anginal / vasodilator
  Vasopressin   Other
  Venlafaxine   Psychiatric drug – Other
  Voriconazole   Antibiotic – Antifungal
  Zimeldine*   Psychiatric drug – Other
  Ziprasidone   Psychiatric drug – Other
  Zolmitriptan   Anti-migraine


Listed by type

Class 1: ajmaline*, cibenzoline*, dihydroquinidine*, disopyramide, encainide*, flecainide, mexiletine, pirmenol*, procainamide, propafenone quinidine*
Class 3: almokalant*, amiodarone, azimilide*, bretylium, dofetilide*, dronedarone*, d-sotalol*, ersentilide*, ibutilide*, nifekalant*, sematilide*, sotalol, terikalant*

bepridil*, lidoflazine*, prenylamine*, ranolazine, terodiline*, vardenafil


indapamide, isradipine, moexipril/hydrochlorthiazide, nicardipine

astemizole*, azelastine, diphenhydramine, ebastine*, hydroxyzine, terfenadine*

Serotonin agonists and antagonists
cisapride*, dolasetron, granisetron, ketanserin*, ondansetron

Macrolide antibiotics: azithromycin, clarithromycin, erythromycin, roxithromycin*, spiramycin, telithromycin
Quinolone antibiotics: ciprofloxacin, gatifloxacin*, gemifloxacin*, grepafloxacin*, levofloxacin, moxifloxacin, ofloxacin, sparfloxacin*
Antifungals: cotrimoxazole, fluconazole (caution with itraconazole), ketoconazole, voriconazole
Others: pentamidine, trimethoprim sulfa (bactrim)
Antiviral: foscarnet (HIV)

amantidine, chloroquine, halofantrine*, quinine

Psychiatric drugs
Tricyclic antidepressants: amitriptyline, amoxapine*, clomipramine, desipramine*, doxepin, imipramine, nortriptyline, protriptyline*, trimipramine
Phenothiazines: chlorpromazine, fluphenazine, prochlorperazine, thioridazine*, trifluoperazine
Others: atomoxetine, citalopram, clozapine, droperidol*, fluoxetine, haloperidol, levomethadyl*, lithium, maprotiline, mesoridazine, methadone, paroxetine, pericycline, pimozide, quetiapine, risperidone, sertindole, sertraline, trazodone, venlafaxine, zimeldine*, ziprasidone

felbamate*, fosphenytoin (prodrug of phenytoin)

naratriptan, sumatriptan, zolmitriptan

arsenic trioxide, geldanamycin*, sunitib, tacrolimus, tamoxifen

alfuzosin, chloral hydrate, clobutinol*, domperidone, galantamine, octreotide, organophosphates*, perflutren lipid microspheres, probucol, solifenacin, tizanidine, tolterodine, vasopressin

Stimulant drugs
Some cold remedies contain these drugs so it is important always to check the label.
adrenaline (epinephrine), amphetamine, cocaine, dexmethylphenidate, dobutamine, dopamine, ephedrine, fenfluramine, isoprenaline (isoproterenol), levalbuterol, metaproterenol, methylphenidate, midodrine, norepinephrine (noradrenaline), phentermine, phenylephrine, phenylpropanolamine, pseudoephedrine, ritodrine, salbutamol (albuterol), salmeterol, sibutramine, terbutaline