Nexterone is an antiarrhythmic medication that affects the rhythm of heartbeats.

Nexterone injection is used to help keep the heart beating normally in people with life-threatening heart rhythm disorders of the ventricles (the lower chambers of the heart that allow blood to flow out of the heart). Nexterone is used to treat or prevent ventricular tachycardia or ventricular fibrillation.

Nexterone injection is for use only in life-threatening situations.

Nexterone injection is for use only in life-threatening situations. You will receive this medicine in a hospital setting.

You should not receive Nexterone if you are allergic to amiodarone or iodine, or if you have a serious heart condition such as "AV block" (unless you have a pacemaker), a history of slow heart beats, or if your heart cannot pump blood properly.

Nexterone is given as an infusion into a vein. Nexterone injection is often given directly into a large vein in the upper chest (central IV line). You will receive this injection in a clinic or hospital setting where your heart can be monitored in case the medicine causes serious side effects.

Your blood will need to be tested often, and you may need eye exams and chest x-rays.

If you need surgery (including laser eye surgery), tell the surgeon ahead of time that you have received Nexterone injection.

Nexterone can affect the results of certain medical tests. Tell any doctor who treats you that you are using Nexterone.

After treatment with Nexterone injection, your doctor may switch you to an oral form of amiodarone to take by mouth. Be sure to read all medication guides or instruction sheets for oral amiodarone.

Usual Adult Dose of Nexterone for Arrhythmias:

IV:
Initial dose: 1000 mg over the first 24 hours of therapy, delivered by the following infusion regimen:
-Loading infusions: 150 mg over the first 10 minutes (15 mg/min), followed by 360 mg over the next 6 hours (1 mg/min)
-Maintenance infusion: 540 mg over the remaining 18 hours (0.5 mg/min)

Maintenance dose: After the first 24 hours, continue the maintenance infusion rate of 0.5 mg/min; may increase infusion rate to achieve effective arrhythmia suppression.
-Supplemental infusions: 150 mg over 10 minutes (15 mg/min) for breakthrough episodes of ventricular fibrillation (VF) or hemodynamically unstable ventricular tachycardia (VT)

Maximum dose: Initial infusion rate: 30 mg/min

Duration of therapy: Until ventricular arrhythmias stabilize (most patients require 48 to 96 hours); maintenance infusion of up to 0.5 mg/min can be continued for up to 3 weeks.

Comments: Mean daily doses greater than 2100 mg for the first 24 hours were associated with increased risk of hypotension.

Use: Initiation of treatment and prophylaxis of frequently recurring VF and hemodynamically unstable VT in patients refractory to other therapy.

You should not receive Nexterone if you are allergic to amiodarone or iodine, or if you have:

• certain serious heart conditions, especially "AV block" (unless you have a pacemaker);
• a history of slow heart beats that have caused you to faint; or
• if your heart cannot pump blood properly.

If possible before you receive Nexterone injection, tell your doctor if you have:

• breathing problems or lung disorder;
• liver disease;
• vision problems;
• high or low blood pressure;
• a thyroid disorder;
• an electrolyte imbalance (such as low levels of potassium or magnesium in your blood);
• if you have recently been ill with vomiting or diarrhea;
• if your heart rhythm disorder has recently become worse; or
• if you have a pacemaker or defibrillator implanted in your chest.

In an emergency situation it may not be possible to tell your caregivers about your health conditions. Make sure any doctor caring for you afterward knows you have received this medicine.

Amiodarone may harm an unborn baby. Tell your doctor if you are pregnant.

You should not breastfeed while receiving Nexterone.

In an emergency situation, it may not be possible before you are treated with Nexterone injection to tell your caregivers if you are pregnant or breast-feeding. Make sure any doctor caring for your pregnancy or your baby knows you have received Nexterone.

Because you will receive Nexterone injection in a clinical setting, you are not likely to miss a dose.

Since this medicine is given by a healthcare professional in a medical setting, an overdose is unlikely to occur.

Avoid getting up too fast from a sitting or lying position, or you may feel dizzy. Get up slowly and steady yourself to prevent a fall.

Grapefruit and grapefruit juice may interact with amiodarone and lead to unwanted side effects. Avoid the use of grapefruit products while you are receiving Nexterone.

Avoid exposure to sunlight or tanning beds. Amiodarone can make you sunburn more easily. Wear protective clothing and use sunscreen (SPF 30 or higher) when you are outdoors.

Get emergency medical help if you have signs of an allergic reaction to Nexterone: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Amiodarone takes a long time to completely clear from your body. You may continue to have side effects from Nexterone after you stop using it. It could take up to several months for the medicine to completely clear from your body.

Call your doctor at once if you have any of these side effects, even if they occur up to several months after you stop using Nexterone:

• a new or a worsening irregular heartbeat pattern;
• fast, slow, or pounding heartbeats;
• a light-headed feeling, like you might pass out;
• wheezing, cough, chest pain, trouble breathing, coughing up blood;
• shortness of breath (even with mild exertion), swelling, rapid weight gain;
• blurred vision, vision loss, headache or pain behind your eyes, sometimes with vomiting;
• swelling, pain, redness, or irritation around your IV needle;
• weight loss, thinning hair, feeling too hot or too cold, increased sweating, irregular menstrual periods, swelling in your neck (goiter);
• pain in your upper stomach, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes); or
• little or no urinating.

Common Nexterone side effects may include:

• low fever;
• slight dizziness; or
• mild nausea, vomiting.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your doctor about all your current medicines. Many drugs can affect amiodarone, especially:

• an antibiotic - azithromycin, ciprofloxacin, clarithromycin, erythromycin, levofloxacin, moxifloxacin, pentamidine, rifampin, and others;
• an antidepressant - amitriptyline, citalopram, desipramine, doxepin, imipramine, nortriptyline, trazodone, and others;
• a blood thinner - warfarin, Coumadin, Jantoven;
• cancer medicines;
• a diuretic or "water pill";
• "statin" cholesterol medicines - atorvastatin, lovastatin, simvastatin, Lipitor, Zocor, Vytorin, and others;
• heart or blood pressure medication - atenolol, carvedilol, clonidine, digoxin, disopyramide, dofetilide, flecainide, ivabradine, metoprolol, nebivolol, procainamide, propranolol, quinidine, sotalol, verapamil, and many others;
• hepatitis C medication - ledipasvir, simeprevir, sofosbuvir, Harvoni, Olysio, Sovaldi;
• HIV or AIDS medication - indinavir, nelfinavir, rilpivirine, ritonavir, saquinavir; or
• medicine to treat mental illness - chlorpromazine, fluphenazine, haloperidol, lithium, pimozide, promethazine, thioridazine, ziprasidone, and others.

This list is not complete and many other drugs may interact with amiodarone. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Amiodarone takes a long time to completely clear from your body, and drug interactions are possible for up to several months after you stop using Nexterone injection. Talk to your doctor before taking any medication during this time. Keep track of how long it has been since your last dose of amiodarone.