Drug Interactions between hydroxyzine and pentamidine

Alcohol can increase the nervous system side effects of hydrOXYzine 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 hydrOXYzine. Do not use more than the recommended dose of hydrOXYzine, 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.

Pentamidine may have direct toxic effects on beta cells of the pancreas. Hypoglycemia, which may be severe and/or prolonged, as well as hyperglycemia and insulin-dependent diabetes mellitus, the latter of which may be irreversible, have been reported. The onset of pentamidine-induced hypoglycemia generally varied from 5 to 7 days after start of therapy to several days after therapy stops. In some cases, hyperglycemia and progression to diabetes followed, although these effects have occurred independently also. Pancreatic toxicity has been reported with both parenteral use and, less frequently, oral inhalation of pentamidine. The risk appears to be related to total cumulative dosage and prior therapy with the drug, particularly within the last 3 months. Therapy with pentamidine, regardless of route of administration, should be administered cautiously in patients with or predisposed to diabetes or spontaneous hypoglycemia. Blood glucose should be monitored more closely during and for some time after pentamidine therapy.

Acute and potentially fatal pancreatitis has been reported with parenteral use and, rarely, oral inhalation of pentamidine. Patients with a history of or known risk factors for pancreatitis, such as alcohol abuse or hypertriglyceridemia, should be monitored closely during therapy with pentamidine. Therapy should be discontinued at the first signs or symptoms suggestive of pancreatitis (e.g., nausea, vomiting, abdominal pain, hyperamylasemia with dysglycemia, rising triglycerides, decreasing serum calcium), and preferably permanently discontinued if clinical pancreatitis develops.

Hematologic toxicities have been associated occasionally with the parenteral use of pentamidine. Leukopenia and, less frequently, thrombocytopenia have been reported and may be severe (e.g., leukocyte count < 1000/mm3, platelet count < 20,000/mm3). Anemia, neutropenia, pancytopenia, and prolonged clotting time have occurred rarely. Therapy with pentamidine should be administered cautiously in patients with preexisting blood dyscrasias and/or bone marrow depression. Complete blood counts, including platelets, should be performed prior to and periodically during and after therapy. Marked depression of blood counts may be indication for withdrawal of pentamidine therapy.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Parenteral use of pentamidine may be associated with serious and potentially fatal cardiovascular effects. Sudden and severe hypotension, cardiorespiratory arrest, ventricular tachycardia, torsade de pointes, ECG abnormalities, and facial flushing have been reported. Therapy with pentamidine should be administered cautiously in all patients but in particular, those with preexisting hypotension, severe cardiovascular disease, or conditions that could be exacerbated by hypotension such as a history of myocardial infarction, angina, or ischemic stroke. Patients should be in a supine position and blood pressure monitored closely during and after administration of the drug until blood pressure is stable. Equipment for emergency resuscitation should be readily available if the parenteral route is used. ECGs should also be performed before, during, and after parenteral therapy.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Parenteral use of pentamidine may be associated with serious and potentially fatal cardiovascular effects. Sudden and severe hypotension, cardiorespiratory arrest, ventricular tachycardia, torsade de pointes, ECG abnormalities, and facial flushing have been reported. Therapy with pentamidine should be administered cautiously in all patients but in particular, those with preexisting hypotension, severe cardiovascular disease, or conditions that could be exacerbated by hypotension such as a history of myocardial infarction, angina, or ischemic stroke. Patients should be in a supine position and blood pressure monitored closely during and after administration of the drug until blood pressure is stable. Equipment for emergency resuscitation should be readily available if the parenteral route is used. ECGs should also be performed before, during, and after parenteral therapy.

Patients who are dehydrated may be particularly susceptible to the nephrotoxic and hypotensive effects associated with the parenteral use of pentamidine. Dehydration should preferably be corrected prior to initiation of therapy. In patients who may be at risk for dehydration, such as those with severe and/or prolonged diarrhea or vomiting, fluid status and blood pressure should be monitored closely. If signs of renal irritation develop during therapy, hydration should be increased as indicated, accompanied by a reduction in dosage if necessary. Therapy should be withdrawn if urinary output decreases progressively or azotemia increases.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

A variety of abnormal thinking and behavior changes have been reported to occur in association with the use of most anxiolytics, sedatives and hypnotics. Some of these changes include decreased inhibition, aggressiveness, agitation, and hallucinations. These drugs can cause or exacerbate mental depression and cause suicidal behavior and ideation. Therapy with these drugs should be administered cautiously in patients with a history of depression or other psychiatric disorders. Patients should be monitored for any changes in mood or behavior. It may be prudent to refrain from dispensing large quantities of medication to these patients.

Pentamidine may have direct toxic effects on beta cells of the pancreas. Hypoglycemia, which may be severe and/or prolonged, as well as hyperglycemia and insulin-dependent diabetes mellitus, the latter of which may be irreversible, have been reported. The onset of pentamidine-induced hypoglycemia generally varied from 5 to 7 days after start of therapy to several days after therapy stops. In some cases, hyperglycemia and progression to diabetes followed, although these effects have occurred independently also. Pancreatic toxicity has been reported with both parenteral use and, less frequently, oral inhalation of pentamidine. The risk appears to be related to total cumulative dosage and prior therapy with the drug, particularly within the last 3 months. Therapy with pentamidine, regardless of route of administration, should be administered cautiously in patients with or predisposed to diabetes or spontaneous hypoglycemia. Blood glucose should be monitored more closely during and for some time after pentamidine therapy.

Patients who are dehydrated may be particularly susceptible to the nephrotoxic and hypotensive effects associated with the parenteral use of pentamidine. Dehydration should preferably be corrected prior to initiation of therapy. In patients who may be at risk for dehydration, such as those with severe and/or prolonged diarrhea or vomiting, fluid status and blood pressure should be monitored closely. If signs of renal irritation develop during therapy, hydration should be increased as indicated, accompanied by a reduction in dosage if necessary. Therapy should be withdrawn if urinary output decreases progressively or azotemia increases.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Hydroxyzine is contraindicated in patients with a QT prolonged interval. Cases of QT prolongation and Torsade de Pointes have been reported during postmarketing studies. Most of the cases reported occurred in patients with other risk factors for QT prolongation, such as preexisting heart disease, electrolyte imbalances or arrhythmogenic drug use. Therefore, hydroxyzine should be used with caution in patients with risk factors for QT prolongation, congenital long QT syndrome, family history of long QT syndrome or other predisposing conditions, as well as myocardial infarction, uncompensated heart failure, and bradyarrhythmias.

Parenteral use of pentamidine may be associated with serious and potentially fatal cardiovascular effects. Sudden and severe hypotension, cardiorespiratory arrest, ventricular tachycardia, torsade de pointes, ECG abnormalities, and facial flushing have been reported. Therapy with pentamidine should be administered cautiously in all patients but in particular, those with preexisting hypotension, severe cardiovascular disease, or conditions that could be exacerbated by hypotension such as a history of myocardial infarction, angina, or ischemic stroke. Patients should be in a supine position and blood pressure monitored closely during and after administration of the drug until blood pressure is stable. Equipment for emergency resuscitation should be readily available if the parenteral route is used. ECGs should also be performed before, during, and after parenteral therapy.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Parenteral use of pentamidine may be associated with serious and potentially fatal cardiovascular effects. Sudden and severe hypotension, cardiorespiratory arrest, ventricular tachycardia, torsade de pointes, ECG abnormalities, and facial flushing have been reported. Therapy with pentamidine should be administered cautiously in all patients but in particular, those with preexisting hypotension, severe cardiovascular disease, or conditions that could be exacerbated by hypotension such as a history of myocardial infarction, angina, or ischemic stroke. Patients should be in a supine position and blood pressure monitored closely during and after administration of the drug until blood pressure is stable. Equipment for emergency resuscitation should be readily available if the parenteral route is used. ECGs should also be performed before, during, and after parenteral therapy.

Acute and potentially fatal pancreatitis has been reported with parenteral use and, rarely, oral inhalation of pentamidine. Patients with a history of or known risk factors for pancreatitis, such as alcohol abuse or hypertriglyceridemia, should be monitored closely during therapy with pentamidine. Therapy should be discontinued at the first signs or symptoms suggestive of pancreatitis (e.g., nausea, vomiting, abdominal pain, hyperamylasemia with dysglycemia, rising triglycerides, decreasing serum calcium), and preferably permanently discontinued if clinical pancreatitis develops.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Parenteral use of pentamidine may be associated with serious and potentially fatal cardiovascular effects. Sudden and severe hypotension, cardiorespiratory arrest, ventricular tachycardia, torsade de pointes, ECG abnormalities, and facial flushing have been reported. Therapy with pentamidine should be administered cautiously in all patients but in particular, those with preexisting hypotension, severe cardiovascular disease, or conditions that could be exacerbated by hypotension such as a history of myocardial infarction, angina, or ischemic stroke. Patients should be in a supine position and blood pressure monitored closely during and after administration of the drug until blood pressure is stable. Equipment for emergency resuscitation should be readily available if the parenteral route is used. ECGs should also be performed before, during, and after parenteral therapy.

Hydroxyzine is contraindicated in patients with a QT prolonged interval. Cases of QT prolongation and Torsade de Pointes have been reported during postmarketing studies. Most of the cases reported occurred in patients with other risk factors for QT prolongation, such as preexisting heart disease, electrolyte imbalances or arrhythmogenic drug use. Therefore, hydroxyzine should be used with caution in patients with risk factors for QT prolongation, congenital long QT syndrome, family history of long QT syndrome or other predisposing conditions, as well as myocardial infarction, uncompensated heart failure, and bradyarrhythmias.

Hydroxyzine is contraindicated in patients with a QT prolonged interval. Cases of QT prolongation and Torsade de Pointes have been reported during postmarketing studies. Most of the cases reported occurred in patients with other risk factors for QT prolongation, such as preexisting heart disease, electrolyte imbalances or arrhythmogenic drug use. Therefore, hydroxyzine should be used with caution in patients with risk factors for QT prolongation, congenital long QT syndrome, family history of long QT syndrome or other predisposing conditions, as well as myocardial infarction, uncompensated heart failure, and bradyarrhythmias.

Acute and potentially fatal pancreatitis has been reported with parenteral use and, rarely, oral inhalation of pentamidine. Patients with a history of or known risk factors for pancreatitis, such as alcohol abuse or hypertriglyceridemia, should be monitored closely during therapy with pentamidine. Therapy should be discontinued at the first signs or symptoms suggestive of pancreatitis (e.g., nausea, vomiting, abdominal pain, hyperamylasemia with dysglycemia, rising triglycerides, decreasing serum calcium), and preferably permanently discontinued if clinical pancreatitis develops.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Parenteral use of pentamidine may be associated with nephrotoxicity, usually evidenced by elevations in BUN or serum creatinine concentrations. Azotemia has also been reported. Although pentamidine-induced nephrotoxicity is generally mild to moderate in severity and reversible following discontinuation of the drug, acute renal failure has occurred occasionally. Limited evidence suggests that nephrotoxicity may occur more frequently in patients with AIDS and may be accompanied by severe, sometimes life-threatening hyperkalemia. Therapy with pentamidine should be administered cautiously in patients with renal impairment. The need for dosage adjustments is uncertain. To minimize the risk of toxicity, patients should be adequately hydrated and use with other nephrotoxic agents should be avoided. Renal function and serum potassium levels should be closely monitored, and the dosing frequency reduced or therapy withdrawn if toxicity develops.

Hydroxyzine is contraindicated in patients with a QT prolonged interval. Cases of QT prolongation and Torsade de Pointes have been reported during postmarketing studies. Most of the cases reported occurred in patients with other risk factors for QT prolongation, such as preexisting heart disease, electrolyte imbalances or arrhythmogenic drug use. Therefore, hydroxyzine should be used with caution in patients with risk factors for QT prolongation, congenital long QT syndrome, family history of long QT syndrome or other predisposing conditions, as well as myocardial infarction, uncompensated heart failure, and bradyarrhythmias.

Patients who are dehydrated may be particularly susceptible to the nephrotoxic and hypotensive effects associated with the parenteral use of pentamidine. Dehydration should preferably be corrected prior to initiation of therapy. In patients who may be at risk for dehydration, such as those with severe and/or prolonged diarrhea or vomiting, fluid status and blood pressure should be monitored closely. If signs of renal irritation develop during therapy, hydration should be increased as indicated, accompanied by a reduction in dosage if necessary. Therapy should be withdrawn if urinary output decreases progressively or azotemia increases.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

It has been suggested that the anticholinergic effect of antihistamines may reduce the volume and cause thickening of bronchial secretions, resulting in obstruction of respiratory tract. Some manufacturers and clinicians recommend that therapy with antihistamines be administered cautiously in patients with asthma or chronic obstructive pulmonary disease.

Orally inhaled pentamidine may induce bronchospasm and cough. Therapy with aerosolized pentamidine should be administered cautiously in patients with severe bronchospastic disease or a history of extensive smoking. Pretreatment with a beta-2 adrenergic bronchodilator prior to each dose of aerosolized pentamidine may be helpful in patients who experience respiratory symptoms from the medication.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Orally inhaled pentamidine may induce bronchospasm and cough. Therapy with aerosolized pentamidine should be administered cautiously in patients with severe bronchospastic disease or a history of extensive smoking. Pretreatment with a beta-2 adrenergic bronchodilator prior to each dose of aerosolized pentamidine may be helpful in patients who experience respiratory symptoms from the medication.

It has been suggested that the anticholinergic effect of antihistamines may reduce the volume and cause thickening of bronchial secretions, resulting in obstruction of respiratory tract. Some manufacturers and clinicians recommend that therapy with antihistamines be administered cautiously in patients with asthma or chronic obstructive pulmonary disease.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.

Some hypnotic drugs can have an anticholinergic effect and should be used with caution in patients with glaucoma, and trouble urinating due to retention or enlarged prostate.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Antihistamines may infrequently cause cardiovascular adverse effects related to their anticholinergic and local anesthetic (quinidine-like) activities. Tachycardia, palpitation, ECG changes, arrhythmias, hypotension, and hypertension have been reported. Although these effects are uncommon and usually limited to overdosage situations, the manufacturers and some clinicians recommend that therapy with antihistamines be administered cautiously in patients with cardiovascular disease, hypertension, and/or hyperthyroidism.

Limited pharmacokinetic data are available for the older, first-generation antihistamines. Many appear to be primarily metabolized by the liver, and both parent drugs and metabolites are excreted in the urine. Patients with renal and/or liver disease may be at greater risk for adverse effects from antihistamines due to drug and metabolite accumulation. Therapy with antihistamines should be administered cautiously in such patients. Lower initial dosages may be appropriate.

Parenteral use of pentamidine may cause elevated liver function tests. Therapy with pentamidine should be administered cautiously in patients with hepatic impairment. Serum transaminase, alkaline phosphatase, and bilirubin levels should be measured periodically, and the dosing frequency reduced or therapy withdrawn if significant elevations develop.

Some anxiolytics, sedatives and hypnotics are extensively metabolized by the liver, and excreted in the urine. Patients with impaired renal and/or hepatic function may be at greater risk for adverse effects, including central nervous system and respiratory depression, due to drug and metabolite accumulation. Therapy with these drugs should be administered cautiously in such patients, with careful dose selection usually starting at the low end of the dosing range.

In general, anxiolytics, sedatives and hypnotics are extensively metabolized by the liver. Their plasma clearance may be decreased and their half-life prolonged in patients with impaired hepatic function. Therapy with these drugs should be administered cautiously in patients with liver disease (some are not recommended in severe liver impairment), and the dosage should be adjusted accordingly. Laboratory testing is recommended prior and during treatment.

Orally inhaled pentamidine is generally not associated with significant systemic toxicity due to limited absorption from the respiratory tract. However, detectable serum concentrations have been reported in some patients receiving chronic oral inhalation therapy, and systemic adverse effects have occasionally occurred. Therefore, when pentamidine is administered by oral inhalation, clinicians may want to heed the usual warnings and precautions associated with parenteral use of the drug.

Some anxiolytics, sedatives and hypnotics are extensively metabolized by the liver, and excreted in the urine. Patients with impaired renal and/or hepatic function may be at greater risk for adverse effects, including central nervous system and respiratory depression, due to drug and metabolite accumulation. Therapy with these drugs should be administered cautiously in such patients, with careful dose selection usually starting at the low end of the dosing range.

Limited pharmacokinetic data are available for the older, first-generation antihistamines. Many appear to be primarily metabolized by the liver, and both parent drugs and metabolites are excreted in the urine. Patients with renal and/or liver disease may be at greater risk for adverse effects from antihistamines due to drug and metabolite accumulation. Therapy with antihistamines should be administered cautiously in such patients. Lower initial dosages may be appropriate.

Some hypnotic drugs can have an anticholinergic effect and should be used with caution in patients with glaucoma, and trouble urinating due to retention or enlarged prostate.

Antihistamines often have anticholinergic activity, to which elderly patients are particularly sensitive. Therapy with antihistamines should be administered cautiously, if at all, in patients with preexisting conditions that are likely to be exacerbated by anticholinergic activity, such as urinary retention or obstruction; angle-closure glaucoma, untreated intraocular hypertension, or uncontrolled primary open-angle glaucoma; and gastrointestinal obstructive disorders. Conventional, first-generation antihistamines such as the ethanolamines (bromodiphenhydramine, carbinoxamine, clemastine, dimenhydrinate, diphenhydramine, doxylamine, phenyltoloxamine) tend to exhibit substantial anticholinergic effects. In contrast, the newer, relatively nonsedating antihistamines (e.g., cetirizine, fexofenadine, loratadine) reportedly have low to minimal anticholinergic activity at normally recommended dosages and may be appropriate alternatives.