Drug Interactions between Lyrica and tapentadol

Do not use alcohol or medications that contain alcohol while you are receiving treatment with tapentadol. This may increase nervous system side effects such as drowsiness, dizziness, lightheadedness, difficulty concentrating, and impairment in thinking and judgment. In severe cases, low blood pressure, respiratory distress, fainting, coma, or even death may occur. If you are taking certain long-acting formulations of tapentadol, consumption of alcohol may also cause rapid release of the drug, resulting in high blood levels that may be potentially lethal. Extended-release formulations of tapentadol should be swallowed whole (i.E., do not crush, chew, or divide the pill). Talk to your doctor or pharmacist if you have questions on how to take this or other medications you are prescribed. Do not use more than the recommended dose of tapentadol, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medication without first talking to your doctor.

Alcohol can increase the nervous system side effects of pregabalin such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with pregabalin. Do not use more than the recommended dose of pregabalin, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

The use of opiate agonists is contraindicated in patients with acute alcohol intoxication exhibiting depressed vital signs. The central nervous system depressant effects of opiate agonists may be additive with those of alcohol. Severe respiratory depression and death may occur. Therapy with opiate agonists should be administered cautiously in patients who might be prone to acute alcohol intake.

Opiate agonists have the potential to cause dependence and abuse. Tolerance as well as physical and psychological dependence can develop after prolonged use. Abrupt cessation, reduction in dosage, or administration of an opiate antagonist such as naloxone may precipitate withdrawal symptoms. In patients who have developed tolerance to an opiate agonist, overdosage can still produce respiratory depression and death, and cross-tolerance usually will occur with other agents in the class. Addiction-prone individuals, such as those with a history of alcohol or substance abuse, should be under careful surveillance or medical supervision when treated with opiate agonists. It may be prudent to refrain from dispensing large quantities of medication to these patients. After prolonged use or if dependency is suspected, withdrawal of opiate therapy should be undertaken gradually using a dosage-tapering schedule.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

The hypoventilation associated with administration of opiate agonists, particularly by the intravenous route, can induce cerebral hypoxia and vasodilatation with resultant increase in intracranial pressure. Opiate agonists should not be used in patients with suspected or known head injury or increased intracranial pressure. Also, clinicians treating such patients should be aware that opiate agonists may interfere with the evaluation of CNS function, especially with respect to consciousness levels, respiratory status, and pupillary changes.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

The hypoventilation associated with administration of opiate agonists, particularly by the intravenous route, can induce cerebral hypoxia and vasodilatation with resultant increase in intracranial pressure. Opiate agonists should not be used in patients with suspected or known head injury or increased intracranial pressure. Also, clinicians treating such patients should be aware that opiate agonists may interfere with the evaluation of CNS function, especially with respect to consciousness levels, respiratory status, and pupillary changes.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

Opiate agonists can induce vasodilation and significant hypotension, particularly when given in high dosages and/or by rapid intravenous administration. Opiate analgesics cause vasodilatation that may exacerbate hypotension and hypoperfusion and, therefore, are contraindicated in circulatory shock. At therapeutic analgesic dosages, ambulatory patients are more likely to experience dizziness and hypotension than patients who are confined to bed. However, orthostatic hypotension may occur in supine patients upon rising. Therapy with opiate agonists should be administered cautiously and initiated at reduced dosages in patients with hypovolemia, or a predisposition to hypotension. When given by intramuscular or subcutaneous administration, clinicians should also be aware that impaired perfusion in these patients may prevent complete absorption of the drug. With repeated injections, an excessive amount may be absorbed suddenly if normal circulation is reestablished.

Opiate agonists have the potential to cause dependence and abuse. Tolerance as well as physical and psychological dependence can develop after prolonged use. Abrupt cessation, reduction in dosage, or administration of an opiate antagonist such as naloxone may precipitate withdrawal symptoms. In patients who have developed tolerance to an opiate agonist, overdosage can still produce respiratory depression and death, and cross-tolerance usually will occur with other agents in the class. Addiction-prone individuals, such as those with a history of alcohol or substance abuse, should be under careful surveillance or medical supervision when treated with opiate agonists. It may be prudent to refrain from dispensing large quantities of medication to these patients. After prolonged use or if dependency is suspected, withdrawal of opiate therapy should be undertaken gradually using a dosage-tapering schedule.

Anxiolytic, sedative, and hypnotic agents have the potential to cause dependence and abuse. Tolerance as well as physical and psychological dependence can develop, particularly after prolonged use of excessive dosages, and abrupt cessation and/or a reduction in dosage may precipitate withdrawal symptoms. In patients who have developed tolerance, overdosage can still produce respiratory depression and death. Therapy with anxiolytic, sedative, and hypnotic agents should be administered cautiously and for as brief a period as possible. Addiction-prone individuals, such as those with a history of alcohol or substance abuse, should be under careful surveillance or medical supervision when treated with these agents. In addition, it may be prudent to refrain from dispensing large quantities of medication to such patients. After prolonged use or if dependency is suspected, withdrawal of medication should be undertaken gradually using a dosage-tapering schedule.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

Opioid analgesics are contraindicated in patients with known or suspected gastrointestinal obstruction, including paralytic ileus.

The hypoventilation associated with administration of opiate agonists, particularly by the intravenous route, can induce cerebral hypoxia and vasodilatation with resultant increase in intracranial pressure. Opiate agonists should not be used in patients with suspected or known head injury or increased intracranial pressure. Also, clinicians treating such patients should be aware that opiate agonists may interfere with the evaluation of CNS function, especially with respect to consciousness levels, respiratory status, and pupillary changes.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Opiate agonists can induce vasodilation and significant hypotension, particularly when given in high dosages and/or by rapid intravenous administration. Opiate analgesics cause vasodilatation that may exacerbate hypotension and hypoperfusion and, therefore, are contraindicated in circulatory shock. At therapeutic analgesic dosages, ambulatory patients are more likely to experience dizziness and hypotension than patients who are confined to bed. However, orthostatic hypotension may occur in supine patients upon rising. Therapy with opiate agonists should be administered cautiously and initiated at reduced dosages in patients with hypovolemia, or a predisposition to hypotension. When given by intramuscular or subcutaneous administration, clinicians should also be aware that impaired perfusion in these patients may prevent complete absorption of the drug. With repeated injections, an excessive amount may be absorbed suddenly if normal circulation is reestablished.

Narcotic (opioid) analgesic agents may prolong and/or worsen diarrhea associated with organisms that invade the intestinal mucosa, such as toxigenic Escherichia coli, Salmonella, Shigella, and pseudomembranous colitis due to broad-spectrum antibiotics. These agents decrease gastrointestinal motility, which may delay the excretion of infective gastroenteric organisms and/or their toxins. Other symptoms and complications such as fever, shedding of organisms, and extraintestinal illness may also be increased or prolonged. Therapy with opioids should be avoided or administered cautiously in patients with infectious diarrhea, particularly that due to pseudomembranous enterocolitis or enterotoxin-producing bacteria or if accompanied by high fever, pus, or blood in the stool.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

Narcotic (opioid) analgesic agents increase smooth muscle tone in the gastrointestinal tract and decrease peristalsis, which can lead to elevated intraluminal pressure, spasm, and constipation following prolonged use. In patients with severe or acute inflammatory bowel disease, the decrease in colonic motility may induce toxic megacolon. Therapy with opioids should be administered cautiously in patients with gastrointestinal obstruction, constipation, inflammatory bowel disease, or recent gastrointestinal tract surgery. Gastrointestinal effects appear to be the most pronounced with morphine.

The use of narcotic (opioid) analgesic agents is contraindicated in premature infants. These agents may cross the immature blood-brain barrier to a greater extent than in adults, resulting in disproportionate respiratory depression.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Opiate agonists may produce significant central nervous system and respiratory depression of varying duration, particularly when given in high dosages and/or by rapid intravenous administration. Apnea may result from decreased respiratory drive as well as increased airway resistance, and rigidity of respiratory muscles may occur during rapid IV administration or when these agents are used in the induction of anesthesia. At therapeutic analgesic dosages, the respiratory effects are usually not clinically important except in patients with preexisting pulmonary impairment. Therapy with opiate agonists should be avoided or administered with extreme caution and initiated at reduced dosages in patients with severe CNS depression; sleep apnea; hypoxia, anoxia, or hypercapnia; upper airway obstruction; chronic pulmonary insufficiency; a limited ventilatory reserve; or other respiratory disorders. In the presence of excessive respiratory secretions, the use of opiate agonists may also be problematic because they decrease ciliary activity and reduce the cough reflex. Caution is also advised in patients who may be at increased risk for respiratory depression, such as comatose patients or those with head injury, intracranial lesions, or intracranial hypertension. Clinical monitoring of pulmonary function is recommended, and equipment for resuscitation should be immediately available if parenteral or neuraxial routes are used. Naloxone may be administered to reverse clinically significant respiratory depression, which may be prolonged depending on the opioid agent, cumulative dose, and route of administration.

Opiate agonists can induce vasodilation and significant hypotension, particularly when given in high dosages and/or by rapid intravenous administration. Opiate analgesics cause vasodilatation that may exacerbate hypotension and hypoperfusion and, therefore, are contraindicated in circulatory shock. At therapeutic analgesic dosages, ambulatory patients are more likely to experience dizziness and hypotension than patients who are confined to bed. However, orthostatic hypotension may occur in supine patients upon rising. Therapy with opiate agonists should be administered cautiously and initiated at reduced dosages in patients with hypovolemia, or a predisposition to hypotension. When given by intramuscular or subcutaneous administration, clinicians should also be aware that impaired perfusion in these patients may prevent complete absorption of the drug. With repeated injections, an excessive amount may be absorbed suddenly if normal circulation is reestablished.

Pregabalin should be administered cautiously in patients with preexisting conduction abnormalities (e.g., marked first-degree AV block or second- or third-degree AV block), as it has been associated with PR interval prolongation. In a clinical trial, the mean PR interval increase was 3 to 6 msec with pregabalin at doses higher than or equal to 300 mg per day. This mean change difference was not associated with an increased risk of PR increase >=25% from baseline, an increased percentage of subjects with on-treatment PR >200 msec, or an increased risk of adverse reactions of second or third degree AV block. Subgroup analyses did not identify an increased risk of PR prolongation in patients with baseline PR prolongation or in patients taking other PR prolonging medications. However, these analyses cannot be considered definitive because of the limited number of patients in these categories.

Angioedema has been reported during pregabalin therapy, including reports of life-threatening angioedema with respiratory compromise requiring emergency treatment. Therapy with pregabalin should be administered cautiously in patients at risk of developing angioedema or those with a previous episode of angioedema.

Opioid agonists may cause spasm of the sphincter of Oddi, which may increase biliary tract pressure. Other opioid-induced effects may include a reduction in biliary and pancreatic secretions and transient elevations in serum amylase. Patients with biliary tract disease (including acute pancreatitis) should be regularly evaluated for worsening symptoms. Therapy with opioids should be administered cautiously in patients with biliary tract disease, gallbladder disease, or acute pancreatitis.

Pregabalin treatment may cause peripheral edema. There are limited data concerning the use of pregabalin in patients with congestive heart failure. Therapy with pregabalin should be administered cautiously in patients with New York Heart Association (NYHA) Class III or IV cardiac status.

Antiepileptic drugs (AEDs) have been associated with an increased risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Pooled analyses of 199 placebo-controlled clinical studies involving the use of 11 different AEDs showed that patients receiving AEDs had approximately twice the risk of suicidal thinking or behavior compared to patients receiving placebo. AEDs should be administered cautiously in patients with depression or other psychiatric disorders; phentermine-topiramate should be avoided in patients with history of suicidal attempts or active suicidal ideation. The risk of suicidal thoughts and behavior should be carefully assessed against the risk of untreated illness, bearing in mind that epilepsy and many other conditions for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior. Patients, caregivers, and families should be alert to the emergence or worsening of signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts or behavior. If patients have symptoms of suicidal ideation or behavior, a dosage reduction or treatment discontinuation should be considered.

Opioid agonists may cause spasm of the sphincter of Oddi, which may increase biliary tract pressure. Other opioid-induced effects may include a reduction in biliary and pancreatic secretions and transient elevations in serum amylase. Patients with biliary tract disease (including acute pancreatitis) should be regularly evaluated for worsening symptoms. Therapy with opioids should be administered cautiously in patients with biliary tract disease, gallbladder disease, or acute pancreatitis.

Pregabalin should be administered cautiously in patients with preexisting conduction abnormalities (e.g., marked first-degree AV block or second- or third-degree AV block), as it has been associated with PR interval prolongation. In a clinical trial, the mean PR interval increase was 3 to 6 msec with pregabalin at doses higher than or equal to 300 mg per day. This mean change difference was not associated with an increased risk of PR increase >=25% from baseline, an increased percentage of subjects with on-treatment PR >200 msec, or an increased risk of adverse reactions of second or third degree AV block. Subgroup analyses did not identify an increased risk of PR prolongation in patients with baseline PR prolongation or in patients taking other PR prolonging medications. However, these analyses cannot be considered definitive because of the limited number of patients in these categories.

Narcotic (opioid) analgesic agents are extensively metabolized by the liver, and several of them (e.g., codeine, hydrocodone, meperidine, methadone, morphine, propoxyphene) have active metabolites that are further converted to inactive substances. The serum concentrations of these agents and their metabolites may be increased and the half-lives prolonged in patients with impaired hepatic function. Therapy with opioids should be administered cautiously and initiated at reduced dosages in patients with liver disease. Subsequent doses should be titrated based on individual response rather than a fixed dosing schedule.

The use of pregabalin has been associated with creatine kinase elevations. Use caution when treating patients with diagnosed of suspected myopathy or with significantly elevated creatine kinase levels.

Opioid agonists may cause spasm of the sphincter of Oddi, which may increase biliary tract pressure. Other opioid-induced effects may include a reduction in biliary and pancreatic secretions and transient elevations in serum amylase. Patients with biliary tract disease (including acute pancreatitis) should be regularly evaluated for worsening symptoms. Therapy with opioids should be administered cautiously in patients with biliary tract disease, gallbladder disease, or acute pancreatitis.

Antiepileptic drugs (AEDs) have been associated with an increased risk of suicidal thoughts or behavior in patients taking these drugs for any indication. Pooled analyses of 199 placebo-controlled clinical studies involving the use of 11 different AEDs showed that patients receiving AEDs had approximately twice the risk of suicidal thinking or behavior compared to patients receiving placebo. AEDs should be administered cautiously in patients with depression or other psychiatric disorders; phentermine-topiramate should be avoided in patients with history of suicidal attempts or active suicidal ideation. The risk of suicidal thoughts and behavior should be carefully assessed against the risk of untreated illness, bearing in mind that epilepsy and many other conditions for which AEDs are prescribed are themselves associated with morbidity and mortality and an increased risk of suicidal thoughts and behavior. Patients, caregivers, and families should be alert to the emergence or worsening of signs and symptoms of depression, any unusual changes in mood or behavior, or the emergence of suicidal thoughts or behavior. If patients have symptoms of suicidal ideation or behavior, a dosage reduction or treatment discontinuation should be considered.

Although narcotic (opioid) analgesic agents are generally metabolized by the liver, renal impairment can alter the elimination of these agents and their metabolites (some of which are pharmacologically active), resulting in drug accumulation and increased risk of toxicity. Therapy with opioids should be administered cautiously and initiated at reduced dosages in patients with significantly impaired renal function. Subsequent doses should be titrated based on individual response rather than a fixed dosing schedule.

Narcotic (opioid) analgesic agents may increase the frequency of seizures in patients with seizure disorders, may increase the risk of seizures occurring in other clinical settings associated with seizures, and, at higher dosages, have been reported to induce seizures in patients without history of seizures. Patients with history of seizure disorders should be regularly evaluated for worsened seizure control during therapy. Prolonged meperidine use may increase the risk of toxicity (e.g., seizures) from the accumulation of the active metabolite (normeperidine).

Narcotic (opioid) analgesic agents may inhibit the urinary voiding reflex and increase the tone of the vesical sphincter in the bladder. Acute urinary retention requiring catheterization may occur, particularly in patients with prostatic hypertrophy or urethral stricture and in older adult patients. These agents may also decrease urine production via direct effects on the kidney and central stimulation of the release of vasopressin. Therapy with opioids should be administered cautiously in patients with or predisposed to urinary retention and/or oliguria. The effects on smooth muscle tone appear to be the most pronounced with morphine.