Numerous health and social relationship problems, namely an increased risk of contracting HIV, mortality, crime, unemployment and impaired interpersonal relationships, are related to drug dependence, with opioids at the helm. For this reason, opioid addiction is considered a major public health problem [1] and is characterized as a ‘chronic relapsing disease’ and is a major concern for public health, as are drug and alcohol addictions [1, 2]. In addition to social support and psychotherapy, treatment of opioid dependence relies on medication intake. The three main opioid-dependence treatment categories include opioid agonists, opioid antagonists, and non-opioid medications. Naltrexone hydrochloride (API), one of the most commonly used medications relies on an opioid antagonist. It reduces opioid cravings, it can be administered outside the hospital setting and cannot be abused [3]. However, during treatment several patients often forget to take a dose, doubling the next dose to compensate. In some cases, this finding in the therapeutic levels not being reached, while in other cases undesired (side) effects appear. For this reason, especially in the case of long-term treatments of numerous diseases, an extended dosing interval is recommended, so that the patient receives the drug, only once a day, instead of two or three times a day.