This list includes medications which prolong the QT interval and is meant as a guide for people with Long QT syndrome, or acquired long QT interval from heart muscle disease, and their parents or guardians. It should not be seen as all inclusive. Those prescribing any medication to someone with Long QT syndrome should always check the drug specifications and contra-indications. The list has been compiled by review of publications and/or drug advice sheets provided with medications. Check also www.SADS.org and www.Torsades.org.
Erythromycin, Clarithromycin, Gatifloxacin, levofloxacin, Moxifloxacin
Sulfamethoxazole-trimethoprim (Septrin/Bactrim), Spiramycin, Pentamidine
Terfenadine, Astemizole, Diphenhydramine,
(These are particularly to be avoided (even in normal subjects) in combination with Erythromycin or grapefruit juice or the antifungals ketoconazole, miconazole, fluconazole or itraconazole)
Fenfluramine, phentermine, Sibutramine
The Beta-2 agonists (eg. Terbutaline, Salbutamol, Salmeterol) both work against the B-Blockers given to subjects with long QT and lower blood potassium levels and therefore should be given only in hospital with careful monitoring. Inhaled steroids (eg. Becotide/Flixotide) and Ipatropium (Atrovent) are safer.
Ephedrine,
phenylephrine, phenylpropanolamine, pseudoephedrine
Psychotropics/ Antidepressants/ Anticonvulsants
The antipsychotics (including Thioridazine, Haloperidol Mesoridazine, chlorpromazine), the antidepressants (including Maptiline, Amitriptyline, imiprmaine, fluoxetine, desipramine, paroxetine) and anticonvulsants Felbamate and Fosphenytoin are to be avoided.
Vasodilators (used to dilate blood vessels in treatment of heart failure angina or high blood pressure)
Prenylamine Lidoflazine, Fenoxedil, Bepridil
The others are not safe eg.
Type IA Quinidine (particularly dangerous), Procainamide, Disopyramide
Type IC Encainide, Flecainide
Type III Ibutilide, Amiodarone, Sotalol, Sematilide
Liquorice
This lowers potassium level even in small doses, and is dangerous in big doses (more than one liquorice twist) or over long periods. Is present as Glycyrrhizinic acid (GZA), found in many sweets including Stimorol and Ben Bits Coolmint chewing gum, Fisherman’s Friend, Turkish Pepper and herbal medicines for gastric ulcer treatments. Drinks include Belgian beers, Pastis, Raki, Ouzo and Pernod.
Adrenaline (epinephrine), Amantadine (antiviral and Parkinson’s disease agent), Chloral hydrate (sedative), Cortocosteroids, diuretics (via electrolyte disturbance-low potassium, magnesium, calcium: Frusemide and other loop diuretics particularly dangerous), Chloroquine (antimalarial), Cocaine, Dopamine, dobutamine (used in intensive care), Dolasetron (anti-emetic), Droperidol (sedative), Foscarnet (antiviral), Halofantrine (antimalarial), Isoproterenol (adrenaline like substance), Levomethadyl (narcotic dependance), [1]Midodrine (to treat low blood pressure), Suxamethonium and Atropine (anaesthetic agents), Ritodrine, Vasopressin, Cisapride (for oesophageal reflux- indigestion), Tacrolimus (to suppress immune responses), liquid protein diets. Your dentist should use local anaesthetic WITHOUT ADRENALIN.