Some possible causes of numbness in the fingertips are Raynaud's phenomenon and carpal tunnel syndrome, according to Mayo Clinic and WebMD. Raynaud's phenomenon is a circulatory system disorder, while carpal tunnel syndrome involves the nerves in the hand and wrist.
The symptoms of carpel tunnel syndrome most commonly affect the thumb, part of the ring finger and the middle and index fingers, says WebMD. The symptoms are more noticeable at night and sometimes can be relieved temporarily by shaking the affected hand. Diabetes, hypothyroidism, pregnancy and rheumatoid arthritis increase the risk of carpal tunnel syndrome.
Raynaud's phenomenon, or Raynaud's disease, causes the patient's fingers to feel numb and cold due to stress or cold temperatures, says Mayo Clinic.