1 What is Pronestyl?

Brand: Pronestyl

Generic: Procainamide

Pronestyl injection is a prescription-only medication used when you have irregular or rapid heartbeats.

Pronestyl slows down your heart’s impulses and makes heart tissues less responsive to these impulses. In the US, oral procainamide is no longer in use.

This product is available as:

  • Solution
Have a question aboutIrregular Heartbeat?Ask a doctor now

2 What to Know Before Using

Before using Pronestyl, you must know all about the risks and complications associated with it. Together with your doctor, you can decide whether the medication will provide you more goods than the harms.

Here are some factors to be considered before deciding to use this medicine:

  • Allergies: Inform your doctor about the allergies you have, such as to this medication, other medications, or to foods, dyes, or preservatives.
  • Pediatric: Due to the lack of proper studies, it’s not clear if using this medication for kids is safe or effective.
  • Geriatric: It’s not clear if using this medication is safe or effective in geriatric patients. Your doctor may use adjusted doses of procainamide injection in patients with age-related kidney problems, after assessing the risks and benefits.
  • Pregnancy: Procainamide (intravenous-route) falls under category C for all trimesters, meaning that due to lack of sufficient studies, it’s not clear if this medication is safe for use in pregnancy.
  • Breastfeeding: No significant negative effects are observed when used by a nursing mother.
  • Drug Interactions: Taking two medicines together can be harmful due to possible interactions. In other cases, even if there is a possible interaction between two medicines your doctor may advise you to take them together after adjusting the dose or issuing precautions. Here is a list of the medicines which in general are not recommended to be used with procainamide injection. Inform your doctor if you are using any of these medicines:

        o Amifampridine
        o Bepridil
        o Cisapride
        o Dronedarone
        o Fingolimod
        o Grepafloxacin
        o Levomethadyl
        o Mesoridazine
        o Pimozide
        o Piperaquine
        o Sparfloxacin
        o Terfenadine
        o Thioridazine
        o Ziprasidone

Though usually not recommended, your doctor may decide, after adjusting dose or frequency of one or both medicines, to use procainamide with any of the following medicines:

        o Acecainide
        o Ajmaline
        o Alcuronium
        o Alfuzosin
        o Amiodarone
        o Amisulpride
        o Amitriptyline
        o Amoxapine
        o Anagrelide
        o Apomorphine
        o Aprindine
        o Aripiprazole
        o Arsenic Trioxide
        o Artemether
        o Asenapine
        o Astemizole
        o Atracurium
        o Azithromycin
        o Bupropion
        o Buserelin
        o Chloral
        o Hydrate
        o Chloroquine
        o Chlorpromazine
        o Ciprofloxacin
        o Cisatracurium
        o Citalopram
        o Clarithromycin
        o Clomipramine
        o Clozapine
        o Crizotinib
        o Dabrafenib
        o Dasatinib
        o Degarelix
        o Delamanid
        o Desipramine
        o Deslorelin
        o Disopyramide
        o Dofetilide
        o Dolasetron
        o Domperidone
        o Donepezil
        o Doxacurium
        o Doxepin
        o Droperidol
        o Enflurane
        o Erythromycin
        o Escitalopram
        o Flecainide
        o Fluconazole
        o Fluoxetine
        o Foscarnet
        o Gallamine
        o Gatifloxacin
        o Gemifloxacin
        o Gonadorelin
        o Goserelin
        o Granisetron
        o Halofantrine
        o Haloperidol
        o Halothane
        o Hexafluorenium
        o Histrelin
        o Hydroquinidine
        o Hydroxychloroquine
        o Ibutilide
        o Iloperidone
        o Imipramine
        o Isoflurane
        o Isradipine
        o Ivabradine
        o Ketoconazole
        o Lapatinib
        o Leuprolide
        o Levofloxacin
        o Lidocaine
        o Lidoflazine
        o Lopinavir
        o Lorcainide
        o Lumefantrine
        o Mefloquine
        o Methadone
        o Metocurine
        o Metronidazole
        o Mifepristone
        o Mivacurium
        o Moricizine
        o Moxifloxacin
        o Nafarelin
        o Nalidixic Acid
        o Norfloxacin
        o Nortriptyline
        o Octreotide
        o Ofloxacin
        o Ondansetron
        o Paliperidone
        o Pancuronium
        o Pasireotide
        o Pazopanib
        o Pentamidine
        o Pipecuronium
        o Pirmenol
        o Posaconazole
        o Prilocaine
        o Probucol
        o Procainamide
        o Promethazine
        o Propafenone
        o Protriptyline
        o Quetiapine
        o Quinidine
        o Quinine
        o Risperidone
        o Rocuronium
        o Salmeterol
        o Sertindole
        o Sevoflurane
        o Sodium Phosphate
        o Sodium Phosphate, Dibasic
        o Sodium Phosphate, Monobasic
        o Solifenacin
        o Sorafenib
        o Sotalol
        o Spiramycin
        o Succinylcholine
        o Sulfamethoxazole
        o Sultopride
        o Sunitinib
        o Tacrolimus
        o Telavancin
        o Telithromycin
        o Tetrabenazine
        o Tizanidine
        o Toremifene
        o Trazodone
        o Trifluoperazine
        o Trimethoprim
        o Trimipramine
        o Triptorelin
        o Tubocurarine
        o Vandetanib
        o Vardenafil
        o Vasopressin
        o Vecuronium
        o Vemurafenib
        o Vinflunine
        o Voriconazole
        o Zolmitriptan
        o Zotepine

Rarely and only when absolutely needed, procainamide injection may be used with Cimetidine even if using them together may put you at risk of certain side effects. In such cases, you may have to take the adjusted dose or change the frequency of intake.

  • Other Interactions: Taking your medicine together with certain foods or items such as alcohol or tobacco may cause undesirable interactions. Talk to your doctor to know if using this medicine with food, alcohol, or tobacco is safe.
  • Other Medical Problems: Certain medical conditions might influence the effects (both positive and adverse) and action of procainamide injection. DO NOT forget to inform your doctor about the following conditions:

        o Heart block
        o Heart rhythm problem (e.g., QT prolongation)
        o Current or past Lupus erythematosus (Do not use procainamide)
        o Heart failure, congestive
        o Myasthenia gravis (May aggravate symptoms)
        o Kidney disease
        o Liver disease (Use cautiously)

3 Proper Usage

Proper usage of Pronestyl requires strict adherence to your doctor’s orders. This medicine is injected into your vein by a nurse.

Initially, only a few doses are given and once you start showing better results, an oral medicine will be given to replace this. Talk to your doctor if you have any query.

4 Precautions to Take

In using Pronestyl, you must be careful and take some precautions as advised by your doctor. Here are some points to consider:

  • When using large doses, some patients may feel dizzy or lightheaded, also common among older patients.
  • Exercise extra precaution to avoid fall.
  • Take special care while doing activities that require you to be alert such as driving or using machines.

5 Potential Side Effects

Consult your doctor immediately if you experience any of the following side effects while using Pronestyl:

Less common:

  • Fever and chills
  • Joint pain or swelling
  • Painful breathing
  • Rash or itching


  • Bleeding, blistering, burning, coldness, skin discoloration, swelling, numbness, infection, pain, tingling or warm sensation at the injection site
  • Confusion
  • Fever or soreness in mouth, gums, or throat
  • Hallucinations (perceiving things that are not present)
  • Depression
  • Easy bleeding or bruising
  • Fatigue or lethargy

Seek emergency help if you develop any symptoms of overdose including:

Mild and non-serious side effects usually go away on their own without requiring medical intervention. You may also ask your doctor to learn more about how you may prevent or reduce the side effects.

Talk to your doctor if the side effects persist or worry you, including:

More common: 

  • Diarrhea
  • Thickened skin at the injection site
  • Reduced hunger

Less common:

The side effects of the medicine are not limited to the ones listed above. Call your doctor immediately if you experience any side effects that are uncommon or worry you. To report side effects to the FDA, contact at 1-800-FDA-1088.