Digoxin Lanoxin Medications

Digoxin Info

What is Digoxin?

Digoxin is a cardiac-glycoside medication that comes from the foxglove plant. It works mainly on the heart, helping it beat more strongly and at a steadier rhythm. In Hong Kong, digoxin is found in several prescription products, most commonly under the brand name Lanoxin and as the generic digoxin.

Medications with Digoxin

In the Hong Kong market you will usually see digoxin supplied as:

• Lanoxin - a branded tablet that contains digoxin as its sole active ingredient.
• Digoxin - generic tablets that may be issued by a variety of manufacturers.

Both forms are available in standard tablet strengths (for example 0.125 mg and 0.25 mg). They are taken orally, although a few hospitals also keep injectable preparations for acute care. The medicines are listed on the Hong Kong Department of Health’s Medicines Registry and can be dispensed only with a prescription.

What Does Digoxin Treat?

Digoxin is primarily used for heart-related conditions. The main indications include:

• Atrial fibrillation - an irregular heartbeat where digoxin helps control the heart rate.
• Heart failure - when the heart cannot pump enough blood; digoxin improves the force of each contraction.
• Supraventricular tachycardia - a rapid rhythm originating above the heart’s ventricles, which may be slowed by digoxin.

Patients of various ages who have these conditions may be prescribed digoxin, provided their doctor decides it is appropriate. In Hong Kong, the drug is approved for these uses by the Department of Health.

How Digoxin Works

Digoxin increases the amount of calcium available to heart muscle cells, which makes each beat stronger. At the same time it slows electrical signals travelling through the heart, helping to keep the rhythm regular. The effect can be felt within a few hours after the first dose, but steady benefits often develop over several days as the level in the blood stabilises.

Safety Information

Common Side Effects

Most people experience only mild, temporary effects such as:

• Nausea or loss of appetite
• Mild headache
• Visual changes like a yellow-green tint (rare)

These symptoms usually resolve on their own or after the prescribing doctor adjusts the dose.

Serious Reactions

Although uncommon, some reactions require urgent medical attention:

• Severe dizziness or fainting
• Rapid, irregular heartbeats
• Breathing difficulty or chest pain

If any of these occur, seek help at the nearest emergency department.

Who Should Be Cautious

Digoxin should be used carefully in certain groups:

• People with severe kidney problems, because the drug is cleared mainly by the kidneys.
• Women who are pregnant or breastfeeding should discuss risks with their obstetric team.
• Individuals with known allergy to digoxin or other cardiac glycosides.

Interaction Awareness

Digoxin can interact with several other medicines and substances:

• Medication classes - diuretics, certain antibiotics (e.g., macrolides), and anti-arrhythmic drugs may affect digoxin levels.
• Alcohol and caffeine - excessive intake can influence how the heart reacts to digoxin.
• Food - high-potassium foods (such as bananas) may reduce digoxin’s effect, while very low potassium can increase toxicity risk.

For a full list of interactions, refer to the specific product information for Lanoxin or the generic digoxin you are using.

What to Know Before Using

Store digoxin tablets at room temperature, away from moisture and direct sunlight. Keep them out of reach of children. The typical course may be short-term for rhythm control or longer-term for chronic heart failure, depending on the individual’s condition. Always follow the instructions printed on the medication label and any additional guidance provided by your pharmacist or prescribing clinician. For detailed usage, dosing, and administration, refer to the information that accompanies your specific medication.

Key Terms

Cardiac glycoside: A class of drugs derived from plants that affect heart muscle contraction. Atrial fibrillation: An irregular, often rapid heart rhythm originating in the upper chambers of the heart. Kidney clearance: The process by which the kidneys remove a drug from the bloodstream.

Information Disclaimer

This article offers general educational information about digoxin as an active substance used in various medicines. Its purpose is to help patients better understand the ingredient and the conditions it is used to treat. It is not a substitute for professional medical advice or for the specific instructions provided with individual products. Medicines containing digoxin may differ in formulation, strength, and directions for use. Always consult the labeling of your particular medication and follow your healthcare provider’s guidance for complete information on proper use, dosage, and safety.