Isoptin 80

Leaflet accompanying the packaging: patient information

Isoptin 40, 40 mg, coated tablets

Isoptin 80, 80 mg, coated tablets

Verapamil hydrochloride

You should carefully read the contents of the leaflet before taking the medicine, as it contains important information for the patient.

• You should keep this leaflet, so that you can read it again if you need to.
• If you have any doubts, you should consult a doctor or pharmacist.
• This medicine has been prescribed specifically for you. Do not pass it on to others. The medicine may harm another person, even if their symptoms are the same as yours.
• If you experience any side effects, including those not listed in the leaflet, you should tell your doctor or pharmacist. See section 4.

Table of contents of the leaflet:

• 1. What is Isoptin and what is it used for
• 2. Important information before taking Isoptin
• 3. How to take Isoptin
• 4. Possible side effects
• 5. How to store Isoptin
• 6. Contents of the packaging and other information

1. What is Isoptin and what is it used for

Isoptin is available in the form of coated tablets containing 40 mg or 80 mg of the active substance - verapamil hydrochloride. Verapamil hydrochloride is a selective calcium antagonist acting directly on the heart muscle.
The action of the medicine is based on the inhibition of calcium ions passing through the cell membrane to the heart muscle cells and vascular smooth muscle cells.
The medicine has antihypertensive and antiarrhythmic effects.
The antihypertensive effect of the medicine is the result of a decrease in peripheral resistance without a significant increase in heart rate. In the case of normal blood pressure, the medicine does not have a significant hypotensive effect.
The antiarrhythmic effect, especially in the case of supraventricular arrhythmias, is based on the slowing of conduction in the atrioventricular node. As a result, depending on the type of arrhythmia, there is a restoration of sinus rhythm and/or normalization of ventricular contractions. The medicine does not change the normal heart rate or only slightly reduces it.
Isoptin is indicated for use in adults, children, and adolescents for the treatment of:

• hypertension
• coronary heart disease (conditions characterized by insufficient oxygen supply to the heart muscle), including:
• chronic stable angina pectoris
• unstable angina pectoris (with increasing pain, pain at rest)
• Prinzmetal's angina
• angina pectoris after myocardial infarction without heart failure, when beta-adrenergic blockers are not indicated
• arrhythmias, such as:
• paroxysmal supraventricular tachycardia, atrial fibrillation/flutter with rapid atrioventricular conduction (except for Wolff-Parkinson-White syndrome [WPW] or Lown-Ganong-Levine syndrome [LGL])

2. Important information before taking Isoptin

When not to take Isoptin

• if you are allergic to verapamil hydrochloride or any of the other ingredients of this medicine (listed in section 6)
• in cardiogenic shock
• in second- or third-degree atrioventricular block (except for patients with a functioning pacemaker)
• in sick sinus syndrome (except for patients with a functioning pacemaker)
• in heart failure with a reduced ejection fraction below 35% and/or pulmonary capillary wedge pressure above 20 mmHg (if not secondary to supraventricular tachycardia responding to verapamil treatment)
• in atrial fibrillation/flutter with an accessory conduction pathway (e.g., Wolff-Parkinson-White syndrome [WPW], Lown-Ganong-Levine syndrome [LGL]). In these patients, there is a risk of developing ventricular tachyarrhythmia, including ventricular fibrillation
• if you are taking ivabradine

Warnings and precautions

Before starting treatment with Isoptin, you should discuss it with your doctor.
Special caution should be exercised in patients:
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with acute myocardial infarction complicated by bradycardia, significant hypotension, or left ventricular dysfunction
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with heart block, first-degree atrioventricular block, bradycardia, asystole
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taking antiarrhythmic drugs, beta-adrenergic blockers
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taking digitalis glycosides
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with heart failure with an ejection fraction above 35%
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with hypotension
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taking statins
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with neuromuscular transmission disorders [myasthenia gravis, Lambert-Eaton syndrome, late stages of Duchenne muscular dystrophy]
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with renal impairment
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with severe liver impairment

Isoptin and other medicines

You should tell your doctor about all the medicines you are taking or have recently taken, including those you plan to take.
Interactions with verapamil are possible with the following medicines:

• alpha-adrenergic blockers (e.g., prazosin, terazosin)
• antiarrhythmic drugs (e.g., flecainide, quinidine)
• bronchodilators (e.g., theophylline)
• antiepileptic and anticonvulsant drugs (e.g., carbamazepine, phenytoin)
• antidepressants (e.g., imipramine)
• antidiabetic drugs (e.g., gliburide)
• drugs for gout (e.g., colchicine)
• antibiotics (e.g., clarithromycin, erythromycin, rifampicin, telithromycin)
• anticancer drugs (e.g., doxorubicin)
• barbiturates (e.g., phenobarbital)
• benzodiazepines and other anxiolytic drugs (e.g., buspirone, midazolam)
• beta-adrenergic blockers (e.g., metoprolol, propranolol)
• digitalis glycosides (e.g., digitoxin, digoxin)
• H2 receptor antagonists (e.g., cimetidine)
• immunomodulating and immunosuppressive drugs (e.g., cyclosporine, everolimus, sirolimus, tacrolimus)
• lipid-lowering drugs (e.g., atorvastatin, lovastatin, simvastatin)
• serotonin receptor agonists (e.g., almotriptan)
• drugs increasing uric acid excretion in the urine (e.g., sulfinpyrazone) ˗ dabigatran (anticoagulant) and direct-acting oral anticoagulants ˗ ivabradine (used in the treatment of heart diseases), see section "When not to take Isoptin" ˗ metformin (used in the treatment of diabetes). Verapamil may reduce the effect of metformin in reducing glucose levels.

Isoptin with food and drink

Interactions with grapefruit juice and products containing St. John's wort extract are also possible.
Additional information on some interactions is provided below.
Antiviral drugs against human immunodeficiency virus (HIV)
Ritonavir may increase verapamil plasma levels, enhancing the effect of the medicine. Caution should be exercised when these drugs are used together, and if necessary, the verapamil dose should be reduced.
Information on increased sensitivity to lithium (neurotoxicity) during concomitant treatment with Isoptin and lithium without changes or with increased lithium serum levels has been reported. However, the addition of Isoptin also resulted in decreased lithium serum levels in patients chronically receiving oral fixed doses of lithium. Patients receiving both drugs should be closely monitored.
Drugs blocking neuromuscular transmission
The medicine may enhance the effect of drugs blocking neuromuscular transmission (curare-like and depolarizing drugs). It may be necessary to reduce the dose of Isoptin and/or the dose of the drug blocking neuromuscular transmission when these drugs are used together.
Acetylsalicylic acid
Increased tendency to bleeding.
Ethanol
Increased ethanol plasma levels.
HMG-CoA reductase inhibitors (statins)
In patients taking Isoptin, treatment with HMG-CoA reductase inhibitors (e.g., simvastatin, atorvastatin, or lovastatin) should be started with the lowest possible dose, which is then adjusted by gradual increase.
If the use of the medicine is started in patients already taking an HMG-CoA reductase inhibitor (e.g., simvastatin, atorvastatin, or lovastatin), it is recommended to consider reducing the statin dose and then readjust it based on serum cholesterol levels.
The likelihood of an interaction with fluvastatin, pravastatin, or rosuvastatin is lower.
Hypotensive, diuretic, and vasodilating drugs
Enhancement of the hypotensive effect.

Pregnancy and breastfeeding

If you are pregnant or breastfeeding, think you may be pregnant, or plan to have a child, you should consult your doctor before taking this medicine.
There are no data on the use of the medicine in pregnant women, and therefore, the medicine can be used during pregnancy only if it is absolutely necessary.
The medicine passes into breast milk in a small percentage. The risk to newborns and infants cannot be excluded. However, due to the possibility of severe side effects in breastfed infants, the medicine can be used during breastfeeding only if it is essential for the mother's health.

Driving and using machines

In some patients, Isoptin may affect the ability to react to such an extent that it impairs the ability to drive vehicles, operate machinery, or work in hazardous conditions. This is especially true during the initial treatment period, during dose increases, when switching from another medicine, and when consuming alcohol. The medicine may increase blood ethanol levels and delay its elimination. Therefore, the effect of alcohol may be enhanced.

Isoptin contains sodium

Isoptin contains less than 1 mmol (23 mg) of sodium per tablet, which means that the medicine is considered "sodium-free".

3. How to take Isoptin

This medicine should always be taken exactly as prescribed by your doctor. If you are unsure, you should consult your doctor or pharmacist.
The dose of the medicine should be adjusted individually, depending on the severity of the disease. Long-term clinical experience has confirmed that in all indications, the daily dose is usually between 240 mg and 360 mg. During long-term treatment, the daily dose should not exceed 480 mg, while during short-term treatment, a higher dose can be used. The duration of treatment is unlimited. After long-term treatment, the medicine should not be stopped abruptly. A gradual reduction in dose is recommended.
Isoptin 40 coated tablets 40 mg should be used in patients who are expected to respond satisfactorily to small doses (e.g., patients with liver failure or the elderly). In patients requiring higher doses (e.g., 240 mg to 480 mg of verapamil hydrochloride per day), Isoptin 80 or Isoptin SR or Isoptin SR-E 240 should be used.
Oral administration. The tablet should be swallowed whole (not chewed or sucked), with a sufficient amount of liquid, preferably during or immediately after a meal.
Adults and adolescents over 50 kg of body weight
Hypertension: 120 mg to 480 mg per day in three divided doses.
Coronary heart disease, paroxysmal supraventricular tachycardia, atrial fibrillation, and atrial flutter: 120 mg to 480 mg per day in three or four divided doses.
Special populations
Children and adolescents (only in arrhythmias)
Up to 6 years of age: 80 mg to 120 mg of verapamil hydrochloride per day in two or three divided doses.
From 6 to 14 years of age: 80 mg to 360 mg of verapamil hydrochloride per day in two, three, or four divided doses.
Renal impairment
When using the medicine in patients with renal impairment, caution should be exercised, and the patient's condition should be closely monitored.
Hepatic impairment
In patients with liver failure, the metabolism of the medicine is impaired to varying degrees, depending on the degree of liver failure, which makes the medicine act stronger and longer. Therefore, special caution should be exercised when determining the dose in patients with liver failure, and small doses should be administered in the initial treatment period (see section Warnings and precautions).

Using a higher than recommended dose of Isoptin

Symptoms
Hypotension, bradycardia, slowing of conduction up to high-degree atrioventricular block and arrest of the sinoatrial node, hyperglycemia, stupor, metabolic acidosis, acute respiratory failure syndrome. Overdose has led to deaths.
Treatment
In the case of an overdose, supportive treatment should be used, individually tailored. In the treatment of intentional overdose of the medicine taken orally, beta-adrenergic stimulation and/or parenteral calcium (calcium chloride) have been used effectively. In the case of clinically significant reactions in the form of hypotension or high-degree atrioventricular block, vasopressor drugs or cardiac pacing should be used, respectively.
In the case of asystole, standard procedures should be used, including beta-adrenergic stimulation (e.g., isoproterenol hydrochloride), other vasopressor drugs, or cardiopulmonary resuscitation. Verapamil hydrochloride cannot be removed from the body by hemodialysis.

Missing a dose of Isoptin

You should not take a double dose to make up for a missed dose.

Stopping treatment with Isoptin

After long-term treatment, the medicine should not be stopped abruptly. A gradual reduction in dose is recommended.

4. Possible side effects

Like all medicines, this medicine can cause side effects, although not everybody gets them.
The most common side effects were: headache, dizziness, gastrointestinal disorders: nausea, constipation, and abdominal pain, as well as bradycardia, tachycardia, palpitations, hypotension, flushing, peripheral edema, and fatigue.
Side effects are listed below by system organ class:
Common(in 1 to 10 patients out of 100):
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central dizziness, headache
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bradycardia
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flushing, hypotension
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constipation, nausea
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peripheral edema
Uncommon(in 1 to 10 patients out of 1,000):
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palpitations, tachycardia
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abdominal pain
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fatigue
Rare(in 1 to 10 patients out of 10,000):
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paresthesia, muscle tremors
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sleepiness
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tinnitus
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vomiting
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excessive sweating
Side effects with unknownfrequency (frequency cannot be estimated from available data):
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hypersensitivity reactions
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extrapyramidal disorders, seizures
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hyperkalemia
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peripheral dizziness
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atrioventricular block (first-, second-, or third-degree), heart failure, arrest of the sinoatrial node, sinus bradycardia, asystole (cardiac arrest)
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bronchospasm, dyspnea
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abdominal discomfort, gingival hyperplasia, intestinal obstruction
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angioedema, Stevens-Johnson syndrome, erythema multiforme, alopecia, pruritus, urticaria, rash, erythematous rash
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arthralgia, muscle weakness, muscle pain
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renal failure
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sexual dysfunction, galactorrhea, gynecomastia
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increased prolactin levels in the blood, increased liver enzyme activity
One case of paralysis (quadriparesis) has been reported after concomitant use of verapamil and colchicine.
If any of the side effects get worse or if you experience any side effects not listed in the leaflet, you should inform your doctor or pharmacist.
If you experience any side effects, including those not listed in the leaflet, you should tell your doctor or pharmacist. Side effects can be reported directly to the Department of Drug Safety Monitoring of the Office for Registration of Medicinal Products, Medical Devices, and Biocidal Products, Al. Jerozolimskie 181C, 02-222 Warsaw, Tel.: +48 22 49 21 301; Fax: +48 22 49 21 309; website: https://smz.ezdrowie.gov.pl
Side effects can also be reported to the marketing authorization holder.
Reporting side effects will help to gather more information on the safety of the medicine.

5. How to store Isoptin

The medicine should be stored out of sight and reach of children.
Do not use this medicine after the expiry date stated on the carton after EXP and on the blister after EXP. The expiry date refers to the last day of the month.
Do not store above 25°C.
Medicines should not be disposed of via wastewater or household waste. You should ask your pharmacist how to dispose of medicines that are no longer needed. This will help protect the environment.

6. Contents of the packaging and other information

What Isoptin contains

The active substance of the medicine is verapamil hydrochloride 40 mg or 80 mg.
The excipients are: calcium hydrogen phosphate dihydrate, microcrystalline cellulose, anhydrous colloidal silica, sodium croscarmellose, magnesium stearate, and the tablet coating: hypromellose, sodium lauryl sulfate, macrogol 6000, talc, titanium dioxide (E171).

What Isoptin looks like and contents of the pack

Isoptin 40 is available in packs containing:
40 tablets
50 tablets
Al/PVC blisters in a cardboard box.
Isoptin 80 is available in packs containing:
40 tablets (4 blisters of 10 tablets)
50 tablets (5 blisters of 10 tablets)
Al/PVC blisters in a cardboard box.

Marketing authorization holder and manufacturer

Marketing authorization holder

Viatris Healthcare Sp. z o.o.
ul. Postępu 21B
02-676 Warsaw

Manufacturer

FAMAR A.V.E. ANTHOUSSA PLANT
Anthoussa Avenue 7
Anthoussa Attiki
15349, Greece
To obtain more detailed information, you should contact the marketing authorization holder:
Viatris Healthcare Sp. z o.o.
ul. Postępu 21B
02-676 Warsaw
Phone: (22) 546 64 00
Date of the last revision of the leaflet:02/2024