Confirmed Proximal Deep Vein Thrombosis: Outpatient Anticoagulation

A 48-year-old woman presents to the emergency department with a three-day history of left calf pain and swelling. She has no shortness of breath or chest pain. On examination, the left leg is swollen from the calf to the thigh, with pitting oedema, warmth and tenderness. The rest of the examination is unremarkable. Her vital signs are stable. She has no past medical history of note, is not pregnant, and takes a combined oral contraceptive pill. She has no known drug allergies. Her weight is 70 kg. Blood tests show a normal full blood count, urea and electrolytes with serum creatinine 0.8 mg/dL and eGFR 95 mL/min/1.73m^2. Liver function tests are normal. A compression ultrasound confirms a proximal DVT in the left popliteal and femoral veins. She is haemodynamically stable and suitable for outpatient management. Your task is to prescribe the anticoagulant regimen for this patient. Please specify the drug, dose, frequency, duration, and provide appropriate counselling.