Dependence physical

Physical dependence is usually defined as the onset of withdrawal symptoms when the drug is abruptly removed. Withdrawal syndrome from opioid dependence is associated with a number of obvious and unpleasant symptoms (Table 14—3). In severe dependence, withdrawal symptoms become evident within 6 to 10 hours after the last dose of the drug, and symptoms reach their peak in the second or third day after the drug has been stopped. Withdrawal symptoms last approximately 5 days. This does not necessarily mean that the individual no longer desires the drug, only that the physical symptoms of withdrawal have ceased. Indeed, an addict may continue to crave the drug after months or years of abstinence. 

There are two types of dependence (i.e., psychological dependence and physical dependence). 

---

Opiates are useful analgesics because they reduce pain sensation without blocking feeling or other sensations. However, they also affect mood, iaduce euphoria, reduce mental acuity, and iaduce physical dependence. They can be immunosuppressive and dismpt other homeostatic processes through... 

Molecular modifications of the morphine skeleton have produced numerous derivatives with antitussive properties, some of which have become commercially significant. Ethyknorphine [76-58-4] (29), a simple homologue of codeine, is prepared by ethylating morphine. It is pharmacologically similar to codeine but is seldom used clinically. Pholcodine [509-67-1] (30), the morpholinoethyl derivative of morphine, is used as an antitussive in a number of European countries. It is about one and a half times as potent as codeine, has Htde or no analgesic activity, and produces minimal physical dependence. The compound is prepared by the amino alkylation of morphine (48). 

Drug addiction is a pathological behavioral syndrome that has to be strictly separated from physical dependence. An individual can be physically dependent on a drug without being addicted to it and vice versa. Transient neuroadaptive processes underlie physical dependence and tolerance to a drug, whereas persistent changes within specific neuronal systems underlie addictive behavior. 

Chronic administration of opiates and alcohol leads to physical dependence a phenomenon, which is only weakly expressed following chronic administration of psychostimulants or other drugs of abuse. Physical dependence results from neuroadaptive intracellular changes to an altered pharmacological state. Abstinence from chronic opiate or alcohol use leads to a variety of physiological and psychological withdrawal symptoms based on these adaptations of the neuronal system. 

Physical dependence on a substance is characterized by the desire or compulsion to continue taking the... 

Controlled substances are the most carefully monitored of all drugs. These drags have a high potential for abuse and may cause physical or psychological dependence Physical dependency is a compulsive need to use a substance repeatedly to avoid mild to severe witii-drawal symptoms it is die body s dependence on repeated administration of a drug. Psychological dependency is a compulsion to use a substance to obtain a pleasurable experience it is die mind s dependence on the repeated administration of a drag. One type of dependency may lead to die odier typa... 

Other—physical dependence, pain at injection site, and local tissue irritation... 

The agonist-antagonists drug can cause opioid witii-drawal symptoms in tiiose who are physically dependent on die opioids. There is an increased risk of respiratory... 

These dm may produce withdrawal symptoms in those physically dependent on the narcotics. The patient must not have taken any opiate for the last 7 to 10 days. Naloxone may prevent die action of opioid antidiarrheals, antitussives, and analgesics. This drug is used cautiously during lactation. 

Administration of sufficient doses of an opioid antagonist after only a single therapeutic dose of morphine results in withdrawal phenomena (Bickel et al. 1987 Heishman et al. 1989 Jones 1979). Some degree of physical dependence... 

Heishman SJ, Stitzer ML, Bigelow GE, et al Acute opioid physical dependence in postaddict humans naloxone dose effects after brief morphine exposure. J Pharmacol Exp Ther 248 127-134, 1989... 

Ator NA, Weerts EM, Kaminski BJ, et al Zaleplon and triazolam physical dependence assessed across increasing doses under a once-daily dosing regimen in baboons. Drug Alcohol Depend 61 69-84, 2000... 

Reynaud M, Petit G, Potard D, et al Six deaths linked to concomitant use of buprenor-phine and benzodiazepines. Addiction 93 1383-1392, 1998 Richards JG, Martin JR Binding profiles and physical dependence liabilities of selected benzodiazepine receptor ligands. Brain Res Bull 43 381-387, 1998... 

Walker BM, Ettenberg A The effects of alprazolam on conditioned place preferences produced by intravenous heroin. Pharmacol Biochem Behav 75 75 80, 2003 Weens EM, Griffiths RR Zolpidem self-injection with concurrent physical dependence under conditions of long-term continuous availability in baboons. Behav Pharmacol 9 285—297, 1998... 

---