Causes

Tiny blood vessels (capillaries) link the smallest parts of your arteries to the smallest parts of your veins. Petechiae appear when capillaries bleed, leaking blood into the skin. A number of things can cause this bleeding, including:

• Prolonged straining
• Medications
• Medical conditions

Prolonged straining

Tiny petechiae of the face, neck and chest can be caused by prolonged straining during activities such as coughing, vomiting, giving birth and weightlifting.

Medications

Petechiae may result from taking some types of medications, including:

• Phenytoin (Cerebyx)
• Penicillin
• Quinine (Qualaquin)

Infectious diseases

Petechiae may be caused by any of a number of fungal, viral and bacterial infections, including:

• Cytomegalovirus (CMV) infection
• Endocarditis
• Meningococcemia
• Mononucleosis
• Rocky Mountain spotted fever
• Scarlet fever
• Sepsis
• Strep throat
• Viral hemorrhagic fevers

Other medical conditions

Petechiae may also be caused by noninfectious medical conditions. Examples include:

• Vasculitis
• Thrombocytopenia (low platelet count)
• Leukemia
• Scurvy (vitamin C deficiency)
• Vitamin K deficiency