Raynaud Syndrome or Phenomenon: What is it? Symptoms, Causes and Treatment

Raynaud’s syndrome is defined as vasospasm that occurs in parts of the hand in response to emotional stress or cold.

They are causing discomfort and reversible color changes (pallor, cyanosis, erythema, or both). Occasionally, other parts such as the nose and tongue are affected. The disorder can be primary or secondary.

The overall prevalence is about 3 to 5%, where women are more affected than men, and younger people are more affected than older people.

The Raynaud syndrome or phenomenon is probably caused by an exaggerated response (α2 adrenergic that triggers vasospasm); however, the mechanism is not yet defined.

Primary Raynaud syndrome is much more frequent than secondary (> 80% of cases), which occurs without symptoms or signs of other disorders.

The phenomenon of secondary Raynaud syndrome is accompanied by various disorders and conditions, primarily connective tissue.


  • Connective tissue disorders.
  • The mixed disease of connective or undifferentiated tissue.
  • Polymyositis
  • Systemic sclerosis.
  • Endocrine disorders
  • Hypothyroidism
  • Hematological disorders.
  • Neoplastic disorders.
  • Carcinoma.
  • Paraneoplastic syndrome
  • Neurological disorders.
  • Carpal tunnel syndrome.
  • Trauma.
  • Cocaine.
  • Nicotine.

Symptoms and signs

The sensations of coldness, burning pain, paresthesias, or intermittent changes in the color of one or more digits are precipitated by exposure to cold, emotional stress, or vibration. All of this can be reversed by eliminating stimuli, as the reheating of hands accelerates the restoration of standard color.


Color changes are restricted throughout the area, which can be three-phase (pallor, followed by cyanosis and then by erythema due to reactive hyperemia), biphasic (cyanosis and erythema), or monophasic (pallor or cyanosis only).

Raynaud’s phenomenon most commonly affects the three middle fingers and rarely the thumb. The vasospasm can last from minutes to hours, but occasionally it is severe enough to cause tissue loss in primary Raynaud’s syndrome.

The connective tissue disorder may progress to gangrene, systemic sclerosis, or severely infected ulcers on the fingertips in the secondary syndrome.


The primary and secondary forms of this syndrome are distinguished clinically, with the support of laboratory studies at the vascular level and blood tests. Vascular laboratory tests include pulse waveforms and digital pressures. The preliminary blood test is the panel for vascular collagen diseases (C-reactive protein, rheumatoid factor, antinuclear, and antibodies).

The clinical findings: The clinical history and physical examination to identify a causative disorder are beneficial but have little diagnostic utility.

The findings suggesting primary Raynaud syndrome are the following:

  • At the beginning of the 30 years of age
  • Severe pain attacks that can be asymmetric and unilateral
  • Ischemic injuries


The treatment of the primary form consists of avoiding having the body cold, quitting smoking if stress is a trigger, and performing relaxation techniques or counseling.

Medications such as:

  • Vasodilators blocking Ca channels (prolonged-release nifedipine)
  • Amlodipine
  • Felodipine
  • Prazosin
  • Topical nitroglycerin paste
  • Clonidine

The treatment of the secondary form focuses on the underlying disorder. Blockers of the Ca or prazosin channel. Antibiotics, analgesics, and sometimes surgical debridement may be necessary for ischemic ulcers. Low doses of aspirin can be given.