Can you take Phenobarbital with Ryna-12X?

PHENobarbital has a major potential interaction with Acute Alcohol Intoxication.

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

PHENobarbital has a moderate potential interaction with Adrenal Insufficiency.

Barbiturates, especially phenobarbital, secobarbital and butabarbital, may diminish the systemic effects of exogenous and endogenous corticosteroids via induction of hepatic microsomal enzymes, thereby accelerating the metabolism of corticosteroids. In addition, barbiturates may interfere with pituitary corticotropin production. Therapy with barbiturates should be administered cautiously in patients with adrenal insufficiency. Patients with borderline hypoadrenalism should be monitored closely, and patients receiving steroid supplementation may require an adjustment in dosage when barbiturates are added to or withdrawn from their medication regimen.

PHENobarbital has a major potential interaction with Alcoholism.

Barbiturates 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. Abrupt cessation and/or a reduction in dosage may precipitate withdrawal symptoms. In patients who have developed tolerance to a barbiturate, 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 barbiturates. 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 barbiturates should be undertaken gradually using a dosage-tapering schedule.

PHENobarbital has a major potential interaction with Altered Consciousness.

Barbiturates should not be administered by injection to patients in shock or coma or who have recently received another respiratory depressant. The hypnotic and hypotensive effects of these agents may be prolonged and intensified in such patients.

PHENobarbital has a major potential interaction with Asphyxia.

Barbiturates may produce severe respiratory depression, apnea, laryngospasm, bronchospasm and cough, particularly during rapid intravenous administration. In usual hypnotic dosages, the degree of respiratory depression produced is similar to that which occurs during physiologic sleep, while at higher dosages, the rate, depth and volume of respiration may be markedly decreased. However, some patients may be susceptible at commonly used dosages, including the elderly, debilitated or severely ill patients, those receiving other CNS depressants, and those with limited ventilatory reserve, chronic pulmonary insufficiency or other respiratory disorders. Therapy with barbiturates should be administered cautiously in these patients. Appropriate monitoring and individualization of dosage are particularly important, and equipment for resuscitation should be immediately available if the parenteral route is used. Barbiturates, especially injectable formulations, should generally be avoided in patients with sleep apnea, hypoxia, or severe pulmonary diseases in which dyspnea or obstruction is evident.

The pyrilamine in Ryna-12X has a moderate potential interaction with Asthma.

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.

The phenylephrine in Ryna-12X has a moderate potential interaction with Benign Prostatic Hyperplasia.

Sympathomimetic agents may cause or worsen urinary difficulty in patients with prostate enlargement due to smooth muscle contraction in the bladder neck via stimulation of alpha-1 adrenergic receptors. Therapy with sympathomimetic agents should be administered cautiously in patients with hypertrophy or neoplasm of the prostate.

PHENobarbital has a moderate potential interaction with Bone Marrow Depression/Low Blood Counts.

Hematologic toxicity, including agranulocytosis, thrombocytopenic purpura and megaloblastic anemia, has been reported rarely during use of barbiturates. Therapy with barbiturates should be administered cautiously in patients with preexisting blood dyscrasias or bone marrow suppression. Blood counts are recommended prior to and periodically during long-term therapy, and patients should be instructed to immediately report any signs or symptoms suggestive of blood dyscrasia such as fever, sore throat, local infection, easy bruising, petechiae, bleeding, pallor, dizziness, or jaundice. Barbiturate therapy should be discontinued if blood dyscrasias occur.

The phenylephrine in Ryna-12X has a major potential interaction with Cardiovascular Conditions and Disorders.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

The pyrilamine in Ryna-12X has a moderate potential interaction with Cardiovascular Conditions and Disorders.

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.

The phenylephrine in Ryna-12X has a major potential interaction with Cerebrovascular Insufficiency.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

The pyrilamine in Ryna-12X has a moderate potential interaction with COPD.

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.

The pyrilamine in Ryna-12X has a major potential interaction with Depression.

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.

PHENobarbital has a moderate potential interaction with Depression.

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.

PHENobarbital has a moderate potential interaction with Depression.

Barbiturates depress the central nervous system and may cause or exacerbate mental depression. Therapy with barbiturates should be administered cautiously in patients with a history of depression or suicidal tendencies. It may be prudent to refrain from dispensing large quantities of medication to these patients.

PHENobarbital has a major potential interaction with Dermatitis, Drug-Induced.

Skin eruptions may precede rare but potentially fatal barbiturate-induced reactions such as systemic lupus erythematosus and exfoliative dermatitis, the latter of which may be accompanied by hepatitis and jaundice. Therapy with barbiturates should be administered cautiously in patients with preexisting drug-induced dermatitis, since it may delay the recognition of a potential reaction to barbiturates. Barbiturate therapy should be withdrawn promptly at the first sign of a dermatologic adverse effect. However, cutaneous reactions may proceed to an irreversible stage even after cessation of medication due to the slow rate of metabolism and excretion of barbiturates. Patients should be advised to promptly report signs that may indicate impending development of barbiturate-related cutaneous lesions, including high fever, severe headache, stomatitis, conjunctivitis, rhinitis, urethritis, and balanitis. Rashes may be more likely to occur with phenobarbital and mephobarbital.

The phenylephrine in Ryna-12X has a moderate potential interaction with Diabetes Mellitus.

Sympathomimetic agents may cause increases in blood glucose concentrations. These effects are usually transient and slight but may be significant with dosages higher than those normally recommended. Therapy with sympathomimetic agents should be administered cautiously in patients with diabetes mellitus. Closer monitoring of blood glucose concentrations may be appropriate.

PHENobarbital has a major potential interaction with Drug Dependence.

Barbiturates 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. Abrupt cessation and/or a reduction in dosage may precipitate withdrawal symptoms. In patients who have developed tolerance to a barbiturate, 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 barbiturates. 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 barbiturates should be undertaken gradually using a dosage-tapering schedule.

The pyrilamine in Ryna-12X has a moderate potential interaction with Gastrointestinal Obstruction.

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.

The phenylephrine in Ryna-12X has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

Sympathomimetic agents can induce transient mydriasis via stimulation of alpha-1 adrenergic receptors. In patients with anatomically narrow angles or narrow-angle glaucoma, pupillary dilation can provoke an acute attack. In patients with other forms of glaucoma, mydriasis may occasionally increase intraocular pressure. Therapy with sympathomimetic agents should be administered cautiously in patients with or predisposed to glaucoma, particularly narrow-angle glaucoma.

The pyrilamine in Ryna-12X has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

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.

The pyrilamine in Ryna-12X has a moderate potential interaction with Glaucoma/Intraocular Hypertension.

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.

PHENobarbital has a major potential interaction with Heart Disease.

The intravenous administration of barbiturates may produce severe cardiovascular reactions such as bradycardia, hypertension, or vasodilation with fall in blood pressure, particularly during rapid infusion. Parenteral therapy with barbiturates should be administered cautiously in patients with hypertension, hypotension, or cardiac disease. The intravenous administration of barbiturates should be reserved for emergency treatment of acute seizures or for anesthesia.

PHENobarbital has a major potential interaction with High Blood Pressure.

The intravenous administration of barbiturates may produce severe cardiovascular reactions such as bradycardia, hypertension, or vasodilation with fall in blood pressure, particularly during rapid infusion. Parenteral therapy with barbiturates should be administered cautiously in patients with hypertension, hypotension, or cardiac disease. The intravenous administration of barbiturates should be reserved for emergency treatment of acute seizures or for anesthesia.

PHENobarbital has a moderate potential interaction with Hyperkinetic Syndrome of Childhood.

Paradoxical reactions characterized by excitability and restlessness may occur in pediatric patients with hyperactive aggressive disorders. Such patients should be monitored for signs of paradoxical stimulation during therapy with barbiturates.

The phenylephrine in Ryna-12X has a major potential interaction with Hyperthyroidism.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

The pyrilamine in Ryna-12X has a moderate potential interaction with 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.

PHENobarbital has a major potential interaction with Hypotension.

The intravenous administration of barbiturates may produce severe cardiovascular reactions such as bradycardia, hypertension, or vasodilation with fall in blood pressure, particularly during rapid infusion. Parenteral therapy with barbiturates should be administered cautiously in patients with hypertension, hypotension, or cardiac disease. The intravenous administration of barbiturates should be reserved for emergency treatment of acute seizures or for anesthesia.

The pyrilamine in Ryna-12X has a moderate potential interaction with Hypotension.

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.

PHENobarbital has a major potential interaction with Liver Disease.

Barbiturates are extensively metabolized by the liver. The plasma clearance of barbiturates may be decreased and the half-lives prolonged in patients with impaired hepatic function. Therapy with barbiturates should be administered cautiously and initiated at reduced dosages in patients with liver disease. Barbiturates are not recommended for use in patients with cirrhosis, hepatic failure, hepatic coma, or other severe hepatic impairment.

The pyrilamine in Ryna-12X has a moderate potential interaction with Liver Disease.

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.

The pyrilamine in Ryna-12X has a moderate potential interaction with Liver Disease.

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.

PHENobarbital has a moderate potential interaction with Panhypopituitarism.

Barbiturates, especially phenobarbital, secobarbital and butabarbital, may diminish the systemic effects of exogenous and endogenous corticosteroids via induction of hepatic microsomal enzymes, thereby accelerating the metabolism of corticosteroids. In addition, barbiturates may interfere with pituitary corticotropin production. Therapy with barbiturates should be administered cautiously in patients with adrenal insufficiency. Patients with borderline hypoadrenalism should be monitored closely, and patients receiving steroid supplementation may require an adjustment in dosage when barbiturates are added to or withdrawn from their medication regimen.

The phenylephrine in Ryna-12X has a major potential interaction with Pheochromocytoma.

Sympathomimetic agents may cause adverse cardiovascular effects, particularly when used in high dosages and/or in susceptible patients. In cardiac tissues, these agents may produce positive chronotropic and inotropic effects via stimulation of beta- 1 adrenergic receptors. Cardiac output, oxygen consumption, and the work of the heart may be increased. In the peripheral vasculature, vasoconstriction may occur via stimulation of alpha-1 adrenergic receptors. Palpitations, tachycardia, arrhythmia, hypertension, reflex bradycardia, coronary occlusion, cerebral vasculitis, myocardial infarction, cardiac arrest, and death have been reported. Some of these agents, particularly ephedra alkaloids (ephedrine, ma huang, phenylpropanolamine), may also predispose patients to hemorrhagic and ischemic stroke. Therapy with sympathomimetic agents should generally be avoided or administered cautiously in patients with sensitivity to sympathomimetic amines, hyperthyroidism, or underlying cardiovascular or cerebrovascular disorders. These agents should not be used in patients with severe coronary artery disease or severe/uncontrolled hypertension.

PHENobarbital has a major potential interaction with Porphyria.

The use of barbiturates is contraindicated in patients with a history of porphyria. Barbiturates may exacerbate acute intermittent porphyria or porphyria variegata by inducing the enzymes responsible for porphyrin synthesis.

The phenylephrine in Ryna-12X has a moderate potential interaction with Prostate Tumor, Benign.

Sympathomimetic agents may cause or worsen urinary difficulty in patients with prostate enlargement due to smooth muscle contraction in the bladder neck via stimulation of alpha-1 adrenergic receptors. Therapy with sympathomimetic agents should be administered cautiously in patients with hypertrophy or neoplasm of the prostate.

PHENobarbital has a moderate potential interaction with Psychosis.

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.

PHENobarbital has a major potential interaction with Pulmonary Impairment.

Barbiturates may produce severe respiratory depression, apnea, laryngospasm, bronchospasm and cough, particularly during rapid intravenous administration. In usual hypnotic dosages, the degree of respiratory depression produced is similar to that which occurs during physiologic sleep, while at higher dosages, the rate, depth and volume of respiration may be markedly decreased. However, some patients may be susceptible at commonly used dosages, including the elderly, debilitated or severely ill patients, those receiving other CNS depressants, and those with limited ventilatory reserve, chronic pulmonary insufficiency or other respiratory disorders. Therapy with barbiturates should be administered cautiously in these patients. Appropriate monitoring and individualization of dosage are particularly important, and equipment for resuscitation should be immediately available if the parenteral route is used. Barbiturates, especially injectable formulations, should generally be avoided in patients with sleep apnea, hypoxia, or severe pulmonary diseases in which dyspnea or obstruction is evident.

PHENobarbital has a major potential interaction with Renal Dysfunction.

The long-acting barbiturate, phenobarbital, is partially eliminated by the kidney. The plasma clearance of phenobarbital may be decreased and the half-life prolonged in patients with impaired renal function. Therapy with phenobarbital should be administered cautiously and initiated at reduced dosages in patients with renal impairment. Since approximately 75% of a mephobarbital dose is metabolized to phenobarbital, the same precaution should be observed with mephobarbital. The remaining barbiturates, which are short- and intermediate-acting, are all negligibly excreted in the urine and may be appropriate alternatives in these patients.

The pyrilamine in Ryna-12X has a moderate potential interaction with Renal Dysfunction.

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.

PHENobarbital has a major potential interaction with Respiratory Arrest.

Barbiturates may produce severe respiratory depression, apnea, laryngospasm, bronchospasm and cough, particularly during rapid intravenous administration. In usual hypnotic dosages, the degree of respiratory depression produced is similar to that which occurs during physiologic sleep, while at higher dosages, the rate, depth and volume of respiration may be markedly decreased. However, some patients may be susceptible at commonly used dosages, including the elderly, debilitated or severely ill patients, those receiving other CNS depressants, and those with limited ventilatory reserve, chronic pulmonary insufficiency or other respiratory disorders. Therapy with barbiturates should be administered cautiously in these patients. Appropriate monitoring and individualization of dosage are particularly important, and equipment for resuscitation should be immediately available if the parenteral route is used. Barbiturates, especially injectable formulations, should generally be avoided in patients with sleep apnea, hypoxia, or severe pulmonary diseases in which dyspnea or obstruction is evident.

PHENobarbital has a major potential interaction with Shock.

Barbiturates should not be administered by injection to patients in shock or coma or who have recently received another respiratory depressant. The hypnotic and hypotensive effects of these agents may be prolonged and intensified in such patients.

The pyrilamine in Ryna-12X has a moderate potential interaction with Urinary Retention.

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.

The pyrilamine in Ryna-12X has a moderate potential interaction with Urinary Retention.

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.

PHENobarbital has a moderate potential interaction with Vitamin D Deficiency.

Rickets and osteomalacia have rarely been reported following prolonged use of barbiturates, possibly due to increased metabolism of vitamin D as a result of enzyme induction by barbiturates. Long-term therapy with barbiturates should be administered cautiously in patients with vitamin D deficiency.