Alcohol abuse has clear effects on the hematologic and immune systems.  It produces macrocytosis  with or without anemia, leucopenia, and or thrombocytopenia. Up to 90% of individuals drinking four or more drinks per day have increased  mean corpuscular volume (MCV 100–110  fL). The macrocytosis may only disappear two to four months after the patient stops alcohol. Individuals with excess alcohol intake appear to be immunocompromised and susceptible to recurrent infections. As high as 80% of hospitalized alcoholics have mild thrombocytopenia which can rebound when alcohol is stopped.