Diosmin: what it is and how it works on your veins

2026-10-07

• Diosmin is the active substance of Phlebodia 600; it belongs to the angioprotector (venotonic) group.
• According to the leaflet, it increases vein tone, reduces venous stasis and improves lymph drainage and microcirculation.
• Indications: heaviness, tiredness and pain in the legs, restless legs syndrome and acute haemorrhoids.
• For venous insufficiency: 1 tablet a day with a meal, usually for a 2-month course.
• It is contraindicated under 18 and in the first trimester, and not recommended while breastfeeding.

At the pharmacy you pick up a box of leg medicine and spot an unfamiliar word among the ingredients: diosmin. Or perhaps your doctor mentioned it, and at home you started wondering whether it is a vitamin, a herbal supplement or a proper medicine.

Let's look at what this substance is, how it acts on the veins and when it is used. Everything we say about indications, doses and restrictions is taken strictly from the official instruction leaflet for Phlebodia 600, in which diosmin is the active substance.

What is diosmin?

Diosmin is the active substance in a number of venotonic medicines. Chemically, it belongs to the flavonoids, a large group of compounds, many of which are found in plants. In a tablet, however, it is a medicinal substance: like any medicine, it has indications, contraindications and possible side effects.

Each tablet of Phlebodia 600 contains 600 mg of diosmin. The tablets are round, biconvex, pink and film-coated. The manufacturer is the French company Innothera (Laboratoires INNOTHERA), and the medicine is marketed by Laboratoire Innotech International.

This substance is found in different medicines, and the amount in one tablet can vary. So always check the strength on the pack and read the leaflet for the specific medicine you are holding.

Pharmacologically, it is classed as an angioprotector, or venotonic agent. Put simply, it acts on the blood vessels: the veins and the smallest vessels, the capillaries. Phlebodia 600 is available without a prescription, but 'over the counter' does not mean 'no need to think': before you start, read the leaflet and talk to a specialist, especially if you have a long-term condition or take other medicines.

How does diosmin work on the veins?

To understand how it works, it helps to recall what happens in chronic venous insufficiency. The vein walls become more stretchy, blood pools in the legs and fluid leaks more easily from the small vessels into the surrounding tissues. This is what causes heaviness, tiredness and discomfort by evening.

According to the leaflet, the substance has several effects:

• it increases vein tone, which means it reduces how much the veins stretch;
• it reduces venous stasis (the pooling of blood);
• it improves lymphatic drainage, the outflow of tissue fluid through the lymph vessels;
• it improves microcirculation: it increases capillary resistance and reduces capillary permeability.

It is also important to understand the limits of this action. Diosmin does not 'remove' varicose veins that have already formed, and it does not replace movement, compression stockings or procedures if your doctor has prescribed them. According to the leaflet, its role is to relieve symptoms.

What is diosmin used for?

According to the leaflet, Phlebodia 600 is indicated for:

• relieving symptoms of lymphovenous insufficiency of the legs: heaviness or tiredness, pain and restless legs syndrome. We explained why heaviness builds up by evening in our article on heavy legs in the evening;
• supportive treatment of microcirculation disorders;
• symptomatic treatment of acute haemorrhoids. To learn how to recognise the condition early, read our article on the early signs of haemorrhoids.

A few words about the terms. Lymphovenous insufficiency is a condition in which the veins and lymph vessels of the legs cope less well with draining blood and tissue fluid. Restless legs syndrome means unpleasant sensations in the legs at rest, usually in the evening and at night, that give you an urge to move them.

Before treating symptoms, it is important to understand their cause. Heavy legs or bleeding when you open your bowels can also be caused by other conditions, so it is best to start with a medical examination.

How should Phlebodia 600 be taken according to the leaflet?

The dose depends on the indication:

• for lymphovenous insufficiency, 1 tablet a day with a meal;
• for acute haemorrhoids, 2–3 tablets a day with meals;
• treatment usually lasts 2 months;
• if you miss one or more doses, simply carry on as usual at your usual dose.

Don't change the dosing on your own: more tablets do not mean faster results. If you feel the treatment is not helping, that is a reason to see a doctor, not to increase the dose.

The leaflet also states clearly when to see a doctor: if symptoms of venous insufficiency do not ease within 2 weeks, or if symptoms of acute haemorrhoids persist after several days of treatment.

Who should not take diosmin?

According to the leaflet, Phlebodia 600 should not be used:

• if you are hypersensitive to diosmin or any of the other ingredients;
• in children and adolescents under 18;
• in the first trimester of pregnancy, as experience of its use is limited; later in pregnancy, only on a doctor's recommendation;
• while breastfeeding, when its use is not recommended.

The full list with details is published in the official instruction. If you are unsure whether the medicine is right for you, show the leaflet to your doctor or pharmacist.

What side effects are possible?

Like any medicine, diosmin can cause unwanted effects. The leaflet lists them by frequency:

• common (up to 1 in 10 people): stomach pain;
• uncommon (up to 1 in 100): allergic reactions (rash, itching, hives, angioedema), bloating, diarrhoea, indigestion, nausea;
• rare (up to 1 in 1,000): vomiting.

Tell your doctor or pharmacist about any side effects. We covered this topic in more detail in our article Phlebodia 600: are there any side effects?

What else is useful to know about the medicine?

• No effect on the ability to drive or operate machinery has been reported.
• Store the tablets below 30 °C and out of the reach of children. In summer, don't leave the pack in a hot car.
• The tablets come in blister strips of 15 or 18.
• If you take other medicines, tell your doctor or pharmacist before starting the course.
• Before buying, check the name, the strength and that the packaging is intact.

The key points

Diosmin is the active substance of the venotonic medicine Phlebodia 600, which is indicated to relieve symptoms of venous insufficiency in the legs and for the symptomatic treatment of acute haemorrhoids. It does not replace movement, paying attention to your body and seeing a doctor, but it can be part of a plan you draw up together with a specialist. Before use, read the instruction leaflet and consult a specialist.

Sources: 1. Instructions for medical use of Phlebodia 600 (Republic of Uzbekistan).

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