The length of time Avinza stays in the system varies from patient to patient. In most cases, Avinza will be naturally cleansed from the body within a matter of days. On average, Avinza has a relatively short half-life of about 24 hours. However, it is an extended-release medication, so it takes longer to release into the body after taking it. Some patients may take longer to rid their bodies of Avinza due to physiological factors such as age, dosage levels, duration of use, metabolism and organ function. The time frame to detect Avinza in the body varies by what kind of test is administered. For example, medications and substances can be detected longer in your hair follicles than in your urine samples. Here are some estimates regarding how long Avinza’s active ingredient, morphine, will stay in your system if you are given a urine, hair or saliva test. Urine: In most cases, morphine can be found in a patient’s urine test up to five days after taking it. Hair: Hair follicles can hold traces of morphine for up to 90 days after it has been taken. Saliva: morphine can be detected in a patient’s blood sample within 36 hours of taking the medication.