Generic Digoxin

Introduction

Digoxin is a cardiac-glycoside medication that belongs to the class of cardiac inotropes. It is primarily used to improve the contractile strength of the heart and to control abnormal heart rhythms. Commercially, digoxin is supplied as a 0.25 mg oral tablet (pill) and is listed in many national formularies for the treatment of congestive heart failure and certain atrial arrhythmias. The drug is produced by several manufacturers; common branded versions include Lanoxin® and Digitek®. In addition to its approved uses, digoxin is sometimes discussed in clinical literature for other cardiovascular applications, although those purposes have not received formal regulatory approval.

What is Digoxin?

Digoxin is the generic version of well-known medications, containing the active cardiac-glycoside digoxin. It is derived from the leaves of Digitalis lanata (the woolly foxglove) and has been used in clinical practice for more than eight decades. The medication is marketed worldwide under brand names such as Lanoxin and Digitek, but the chemical composition is identical to the generic product.

Our online pharmacy provides this generic alternative as a cost-effective treatment option for patients who need a reliable source of digoxin.

How Digoxin Works

Digoxin exerts its therapeutic effect by inhibiting the sodium-potassium ATP-ase pump in cardiac myocytes. This inhibition leads to a modest increase in intracellular sodium, which indirectly raises intracellular calcium via the sodium-calcium exchanger. The elevated calcium enhances the force of myocardial contraction (positive inotropy).

In the atrioventricular (AV) node, digoxin augments vagal tone, slowing conduction and prolonging the refractory period. These electrophysiological actions help control rapid ventricular rates in atrial fibrillation or atrial flutter.

Key pharmacokinetic points:

• Onset of action: clinical effects may be observed within 1-2 hours after the first dose.
• Peak plasma concentration: occurs 1-3 hours after oral administration.
• Half-life: 36-48 hours in patients with normal renal function; prolonged in renal impairment.
• Elimination: primarily renal (≈70 % unchanged), with the remainder excreted in bile.

Conditions Treated with Digoxin

Both indications are listed in the FDA-approved labeling and the European Medicines Agency (EMA) product information for digoxin.

Off-Label and Investigational Uses of Digoxin

• Paroxysmal Supraventricular Tachycardia (PSVT) - Small case series have reported successful conversion of PSVT to sinus rhythm, but the evidence is limited and the drug is not approved for this purpose.
• Adjunct in refractory cardiogenic shock - Some ICU protocols use low-dose digoxin to support myocardial contractility when other inotropes are insufficient; data derive from observational studies.
• Neuropsychiatric research (e.g., Alzheimer’s disease) - Early-phase trials explored digoxin’s effect on cellular calcium regulation, but no definitive therapeutic benefit has been demonstrated.

These applications have not received formal regulatory approval. Patients should only consider off-label use under the direct supervision of a qualified healthcare provider, as safety and efficacy have not been established through large-scale randomized trials.

Is Digoxin the Right Medication for You?

Digoxin is most appropriate for adults who:

• Have stable chronic heart failure with a left-ventricular ejection fraction ≤ 45 % and remain symptomatic despite optimized ACE-inhibitor/ARB, beta-blocker, and diuretic therapy.
• Experience rapid ventricular rates secondary to atrial fibrillation or atrial flutter and require a rate-controlling agent that does not significantly lower blood pressure.

Contraindications (situations where digoxin should not be used) include:

• Known hypersensitivity to digoxin or other cardiac glycosides.
• Ventricular fibrillation or severe ventricular arrhythmias.
• Uncontrolled atrial flutter/fibrillation with a very fast ventricular response (risk of worsening conduction block).
• Significant renal impairment (creatinine clearance < 30 mL/min) without dose adjustment, because reduced clearance raises toxicity risk.

Patients with thyroid disorders, electrolyte abnormalities (especially hypokalemia, hypomagnesemia, or hypercalcemia), or those taking interacting drugs (e.g., amiodarone, verapamil) require careful evaluation before initiating digoxin.

Risks, Side Effects, and Interactions

Common

• Nausea, vomiting, loss of appetite - Gastrointestinal upset occurs in up to 10 % of patients, often early in therapy.
• Visual disturbances - Yellow-green halos, blurred vision, or reduced visual acuity may develop with modest serum levels.
• Fatigue or dizziness - Related to the drug’s effect on heart rate and blood pressure.

Rare

• Arrhythmias - Premature ventricular contractions, atrioventricular block, or new-onset atrial tachycardia may appear, particularly when serum digoxin exceeds the therapeutic window (0.5-2.0 ng/mL).
• Electrolyte-related toxicity - Severe hypokalemia or hyperkalemia can precipitate cardiac events.

Serious

• Life-threatening cardiac arrest - Extremely high digoxin concentrations (> 2.5 ng/mL) can cause profound conduction disturbances leading to asystole.
• Severe hyperkalemia - Particularly in patients with renal failure; paradoxically, digoxin toxicity can raise serum potassium dramatically.

Drug-Drug Interactions

• Amiodarone, quinidine, verapamil, diltiazem - Increase digoxin serum levels by inhibiting its renal clearance.
• Loop diuretics (furosemide, torsemide) - May cause hypokalemia, heightening the risk of digoxin-induced arrhythmias.
• Antibiotics (e.g., erythromycin, clarithromycin) - Raise digoxin concentrations via P-glycoprotein inhibition.

Drug-Food Interactions

• High-fat meals - Can slightly delay absorption but do not significantly alter overall exposure.
• St. John’s wort - May reduce digoxin levels through induction of intestinal P-glycoprotein, potentially diminishing efficacy.

Patients should inform their pharmacist and any prescriber of all current medications, supplements, and herbal products.

Use: Dosing, Missed Dose, Overdose

Standard dosing (adults with normal renal function):

• Initiation dose: 0.25 mg orally once daily.
• Maintenance dose: Adjusted based on serum digoxin concentration, renal function, and clinical response; typical range 0.125 mg-0.5 mg daily.

Titration is performed after at least 6-7 days to allow steady-state concentrations. Serum levels are checked 6-12 days after any dose change.

Missed dose:

• If the missed dose is discovered within 12 hours, take the tablet as soon as remembered.
• If more than 12 hours have passed, skip the forgotten dose and resume the regular schedule. Do not double the dose.

Suspected overdose:

• Symptoms may include severe nausea, vomiting, visual changes, confusion, and cardiac arrhythmias.
• Seek immediate medical attention; treatment may involve activated charcoal (if ingestion was recent) and administration of digoxin-specific antibody fragments (Digoxin-Fab) in life-threatening cases.

Practical precautions:

• Take the tablet with a small amount of water; food does not need to be avoided but maintain a consistent routine.
• Avoid excessive alcohol, as it can potentiate gastrointestinal irritation.
• Do not operate heavy machinery or drive until you know how digoxin affects your alertness and vision.

FAQ

• What should I know about storing digoxin tablets?   Store digoxin at room temperature, away from moisture and direct sunlight. Keep the bottle tightly closed and out of reach of children.

• Can I travel internationally with digoxin?   Yes, but carry a copy of the prescription or a physician’s letter, and keep the medication in its original packaging. Some countries may require documentation for cardiac glycosides.

• Do digoxin tablets contain any common allergens?   Inactive ingredients may include lactose, magnesium stearate, and microcrystalline cellulose. Patients with lactose intolerance or specific excipient allergies should verify the formulation with the supplier.

• How does kidney function affect digoxin dosing?   Because roughly 70 % of digoxin is eliminated unchanged by the kidneys, reduced renal clearance necessitates lower doses and more frequent serum level monitoring to avoid toxicity.

• Is there a difference between brand-name and generic digoxin?   Both contain the same active compound and are bioequivalent. Generic tablets may have different inactive ingredients, which can affect tolerability in a small number of patients.

• Why do some patients develop yellow-green visual halos?   The halos result from digoxin’s effect on retinal photoreceptors and are a classic sign of elevated serum levels, prompting a clinician to check drug concentration.

• Can digoxin be used in patients with atrial fibrillation who are also on anticoagulants?   Yes, digoxin does not interfere with the anticoagulant effect of warfarin, dabigatran, or direct oral anticoagulants; however, regular monitoring of both drugs is advisable.

• What laboratory tests are essential while on digoxin?   Baseline and periodic serum digoxin concentration, renal function (creatinine, eGFR), electrolytes (especially potassium, magnesium), and thyroid function tests are recommended.

• Does digoxin interact with over-the-counter herbal supplements?   Herbs such as St. John’s wort can lower digoxin levels, while ginkgo biloba may increase bleeding risk when combined with anticoagulants and should be used with caution.

• Is there any special advice for women who are pregnant or breastfeeding?   Digoxin crosses the placenta and is excreted in breast milk. It is generally reserved for maternal cardiac indications when benefits outweigh potential fetal or neonatal risks; a specialist’s assessment is required.

Glossary

Sodium-potassium ATP-ase pump

An enzyme on cell membranes that moves sodium out of and potassium into cells; inhibition by digoxin raises intracellular calcium, enhancing heart muscle contraction.

Therapeutic window

The plasma concentration range in which a drug is effective without causing unacceptable toxicity; for digoxin, this is typically 0.5-2.0 ng/mL.

AV-node (atrioventricular node)

A component of the heart’s electrical system that relays impulses from the atria to the ventricles; digoxin slows conduction through this node to control heart rate.

P-glycoprotein

A transporter protein in the intestinal lining and kidneys that pumps certain drugs out of cells; inhibition can increase digoxin absorption and serum levels.

Buying Digoxin from Our Online Pharmacy

Patients who need a reliable source of digoxin can obtain the medication from our online pharmacy. We source the product from licensed, internationally recognized suppliers who adhere to Good Manufacturing Practices, ensuring each tablet meets strict purity and potency standards.

• Cost-effective pricing - By purchasing the generic formulation, you receive the medication at a price close to the manufacturer’s cost, reducing the financial burden of long-term therapy.
• Verified quality - Every batch is accompanied by a certificate of analysis, confirming compliance with regulatory specifications.
• Discrete and reliable delivery - Packages are shipped in unmarked, secure envelopes with optional express service (delivery within 7 days) or standard airmail (approximately 3 weeks).
• Privacy-focused service - As a pharmacy-broker platform, we respect your confidentiality; all communications and shipments are handled with strict data protection measures.

Our service is particularly valuable for patients who encounter limited stock, high co-payments, or insurance restrictions at local pharmacies. By partnering with vetted overseas pharmacies, we provide a safe pathway to obtain digoxin when other avenues are unavailable.

Disclaimer

The information presented about Digoxin is intended for general educational purposes and does not substitute professional medical advice. Treatment choices, including any off-label applications, should be made under the guidance of a qualified healthcare professional. Readers are assumed to be responsible adults capable of making informed health decisions. Our online pharmacy offers access to Digoxin for individuals who may have limited availability through conventional pharmacies or insurance plans, or who are seeking affordable generic alternatives. Always consult a qualified clinician before starting, adjusting, or stopping any medication.