Effects of Galbanum oil on patients pain with osteoarthritis of the knee, blocked randomized, single blind, control with standard medication, single center, phase 2 trial, inclusion criteria: eighteen to eighty years old; at least one knee pain lasting one month; radiographic changes including osteophyte and joint space narrowing(grade 1,2,3); pregnancy test in fertile women.
Exclusion criteria: active infectious disease; skin lesion in knee; renal failure; knee surgery in 2 last months; alcohol or opioid abuse; pregnancy or breastfeeding; allergy to oil, sample size: 30 intervention: intervention group give Galbanum oil, oral acetaminophen and quadriceps femoris exercise and control group give topical Diclofenac gel, oral acetaminophen and quadriceps femoris exercise, intervention time: 4 weeks, primary outcome: knee pain severity, knee stiffness, pain interfering with daily activity and patients quality of life.