Assess the Efficacy and Tolerability of Antistax Film-coated Tablets in Patients With Chronic Venous Insufficiency

Inclusion Criteria:

1. Male or Female

2. 18 years of age or older

3. CVI, Clinical Class 3 and Class 4a according to the CEAP classification

4. Presence of stable edema determined by a pretibial pit after 30 seconds pressure withthe thumb documented by a photo

5. Stable and reproducible status of swelling documented by difference of less than 150gbetween screening and baseline as determined by water displacement method

6. Presence of moderate to severe varicoses (dilated, tortuous veins in the subcutaneoustissue with a diameter of more than 3mm

7. Intensity of leg pain at least 5 cm on the Visual Analogue Scale at baseline andpresence of hyperpigmentation or eczema and presence of moderate to severe edema

8. Willing and able to give written informed consent prior to participation in the trial

9. Patients expected to be compliant (compliance with run-in medication greater than 80%as checked by drug count)

Exclusion Criteria:

1. Decompensated cardiac insufficiency according to the New York Heart Association (NYHA)classification III and IV for cardiac patients

2. Edema not due to venous disease of the legs(e.g. latent cardiac insufficiency, renalinsufficiency, lymphoedema, etc)

3. Severe skin changes, e.g. lipodermatosclerosis

4. Current florid venous ulcer

5. Peripheral arterial disease (ankle/arm pressure index less than 0.9)

6. Untreated or insufficiently controlled hypertension

7. Current acute phlebitis of thrombosis with the last 3 months. Post-thromboticsyndrome, who do not currently receive an anticoagulation treatment can be included inthe trial

8. Renal insufficiency

9. Liver disease; hepatic insufficiency

10. Hyper- or hypocalcemia

11. Malignancies

12. Anamnestic indications of diabetic microangiopathy or polyneuropathy

13. Drug and/or alcohol abuse

14. Severe climacteric complaints; changes in or initiation of post-menopausal hormonereplacement therapy within the last 3 months

15. Immobility

16. Avalvulia

17. Klippel-Trénaunay-Weber-Syndrome

18. State after pulmonary embolism

19. Recognized hypersensitivity to the trial drug ingredients

20. Clinical indication for a specific phlebologic treatment, e.g. compression treatmentphlebectomy, etc Previous Treatments:

21. Compression therapy and/or wearing of support stockings less than 2 weeks prior to thevisit at baseline

22. Venous surgery or sclerotherapy with the last 3 months at the leg used for volumetry

23. Treatment with drugs affecting the veins less than 4 weeks prior to visit 1

24. Changes in or unstable response to treatment with theophylline, cardiac glycosides,ACE-inhibitors, calcium antagonists, or laxatives with the last 2 weeks prior to visit 1 Concomitant Treatment:

25. Compression therapy

26. Diuretics

27. Nitrates

28. Ergot alkaloids

29. All preparations which are used as compounds for venous therapy in CVI (e.g.vasoprotectives for antivaricose therapy, preparations with heparin, sclerosingagents, flavonoid-containing preparations, other phytopharmaceuticals

30. Other drugs active on blood vessels and circulation

31. Extensive use of laxatives

32. Anticipated changes in the intake of hormones, ie contraceptives

33. Scheduled major surgery requiring full anesthesia Other exclusion Criteria:

34. Previously studied under the present protocol

35. Participation in another clinical trial within less than 90 days prior to Visit 1

36. Participation in another clinical trial during the present trial

37. Patient is investigator, co-investigator, trial nurse in this trial or is a relativeof the investigator, co-investigator or trial nurse in this trial

38. Pregnant or nursing women or inadequate birth control methods (this applies to femalesof childbearing potential only; reliable contraceptive methods are hormonalcontraceptives, intrauterine devices, sexual abstinence of sterilization)

39. Patients considered as mentally ill as well as unable to work or with limited workingability, or unable (or only partially able) to follow the spoken or writtenexplanations concerning the trial

40. Patients in bad general health state according to the investigator's judgment