The purpose of this study is to determine whether vardenafil is effective in improving clinical symptoms and peripheral blood flow in patients with primary and secondary Raynaud phenomenon.

Inclusion Criteria:

• raynaud-syndrome (primary or secondary) > 1 year duration
• age ≥ 18 years; ≤ 80 years
• informed consent
• a negative pregnancy test in women of child-bearing age

Exclusion Criteria:

• any unstable organic, psychiatric or addictive disease, which - in the opinion of the investigators - might result in an unsuccessful / unreliable participation or premature termination of the trial

• known contraindications against PDE 5-inhibitors (such as intolerance, therapy with nitrates or inhibitors of CYP3A4, etc.)

• extensive necrosis of the finger tips

• pigmentary retinopathy

• verification as a HbsAg or hepatitis C carrier

• unstable angina

• heart failure (NYHA III or IV)

• valve defects of higher degree (particularly aortic stenosis and hypertrophic obstructive cardiomyopathy)

• myocardial infarction, stroke or life-threatening cardiac arrhythmias within the last 6 months

• uncontrolled atrial fibrillation / -flutter with a heart rate > 100 bpm

• prolonged QTc-interval (> 450 msec)

• congenital long-QT-syndrome

• hypokalemia

• severe acute or chronic liver disease, which might lead to priapism (sickle cell anemia, leucemia)

• hemophilia

• active peptic ulcers

• arterial hypotension (systolic blood pressure at rest <90 mmHg) or

• arterial hypertension(systolic blood pressure at rest >170 mmHg or diastolic blood pressure at rest >110 mmHg)

• malignancy within the last 5 years (except squamous or basal cell skin cancer)

• patients with injuries of the spinal cord or central nervous system

• patients with severe chronic kidney disease (creatinin clearance < 30 ml)

• patients with mild to severe liver disease (Child-Pugh A-C)

• Age below 18 or above 80

• prohibited concomitant medication during the study:

  • nitrates or other NO-donators (including amylnitrit)
  • anticoagulative drugs except inhibitors of thrombocyte function
  • androgens (such as testosterone) or anti-androgens
  • strong inhibitors of cytochrome P4503A4:

• very potent HIV-Protease-inhibitors (ritonavir, indinavir)

• anti-mycotic like itraconazole and ketoconazole (topical applications are allowed)

• erythromycin

• grapefruit-juice or products containing grapefruit-juice

  • other study medications (including placebo) up to 30 days before study inclusion
  • therapy of erectile dysfunction(including sildenafil, sublingual apomorphin, MUSE®, intracavernous injections or vacuum pumps) or other therapies of erectile dysfunction within 4 weeks and during the trial period
  • nebivolol
  • alpha-blockers
  • Calcium antagonists
  • medications prolonging the QT-interval
  • abnormal lab tests like:

• serum-creatinine > 3 mg/dl at visit 1

• GOT and GPT > 3 x reference limit set

• diabetes mellitus with a HbA1c > 9%

• patients who are not willing to disclaim a therapy of their erectile dysfunction with vacuum pumps, intravenous injections, sildenafil or other therapies during the trial

• severe migraine (more than once a moth during the last 6 months)

• intolerance to the study medication

• patients who are not able to understand the information and informed consent due to a mental disorder or linguistic barriers

• persons who are living in a institution directly under federal government control due to a court order

• patients who refuse to renounce drinking grapefruit juice during the trial

• women who are pregnant or lactating

• women who are not protected from a pregnancy (intake of oral contraceptives alone in insufficient; highly effective methods of birth control have to be used with a failure rate <1%; barriers: implants, intrauterine-devices (IUD´s),diaphragm, condoms, abstinence, partner is vasectomized, spermicides)

• patients who participated in other interventional studies within 30 days of study inclusion