Centrifugation: When plasma is required, or when not using a serum gel separator tube, follow these instructions: 1  Draw 12 mL of whole blood for each 5 mL of serum or plasma needed. 2  Centrifuge for at least 15 minutes at 2200-2500 RPM. 3  Pipette the serum or plasma into a clean plastic screw-cap vial and attach the label.
Buccal administration; Naloxone; Naltrexone; opioid antagonist; Pharmacokinetics; First-pass metabolism Summary The opioid antagonists naloxone and naltrexone are both known to undergo extensive first-pass metabolism after oral dosing. The buccal route was investigated as a potential alternative to oral administration. Oral and buccal bioavailabilities of naloxone and naltrexone were determined in rats. Less than 1 % of oral naloxone or naltrexone was bioavailable, but buccal administration resulted in approximately 70% bioavailability for each drug.
A naltrexone implant is a small pellet that is inserted into the lower abdominal wall under local anesthetic. The implant is effective for 3-6 months depending on the type of implant used and releases a controlled amount of naltrexone into the body.The implant works by blocking the effects of opiate drugs.It does this by binding to opiate receptors in the body which prevents opiate drugs like heroin or oxycodone from causing a person to experience the usual high. In blocking the effectiveness of the drug, naltrexone helps to break the cycle of drug use.he implant works by blocking the effects of opiate drugs. It does this by binding to opiate receptors in the body which prevents opiate drugs like heroin or oxycodone from causing a person to experience the usual high. In blocking the effectiveness of the drug, naltrexone helps to break the cycle of drug use.