Dr. Richard W Mattison, New Port Richey FL - MD (Doctor of Medicine) Specialties: Family Medicine. Age: ~42. Address: Morton Plant Mease Primary Care 4619 Little Rd, New Port Richey 34655 (727) 372-9918 (Phone) Procedures: Diabetes, Hypertension (High Blood Pressure), Tonsillitis, Ulcers, Urinary Tract Infection..