Severe side effects of chemotherapy during treatment of malignant disease significantly disrupt patient's mental and physical state. Seventy five-years-old female patient was treated for breast cancer by protocol (operation, radiotherapy, chemotherapy-paclitaxel (CHT-PX) every tree weeks) and for dysthymia and generalized anxiety disorder with escitalopram (ESC). Tramadol (TRA) and clonazepam (KLO) given by oncologist due to severe side effects of CHT-PX: muscle cramps, lower back pain, walking difficulties, had partial results, increased anxiety and drug abuse (TRA doses increase from 100 to 300 mg/day and KLO from 4 to 6 mg/day). Efficiency of pregabalin (PG) in pain and anxiety control during CHT-PX application. The assessment was made by 100 mm visual analogue scale (VAS), which assessed physical symptom severity and Hamilton Anxiety Rating Scale (HAMA) on the first day after CHT-PX application, on the 7th, 14th and 21th day. Effective PG dose was 300 mg/day with EST, KLO and TRA previously taken. On the first day after CHT-PX, patient rated pain level as 9 according to VAS. During TRA and KLO treatment, pain level on VAS was 6 from the 7th till 14th day after CHT-PX, on 21th day deceased to 2. HAMA score was 49. After PG augmentation, according to VAS, pain level was 3 on the 7th day and 0 on 14th day. HAMA score was 20. Tapering off the dose of TRA and KLO started till discontinuation of both medications. Pregabalin efficiency in pain and anxiety control increase compliance of oncological patient and reduce harm of drug abuse.