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Can you take Allopurinol with Poly-D?

6 drug interactions and 35 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

allopurinol pyrilamine

Applies to: allopurinol and Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Allopurinol may cause sedation, drowsiness, dizziness, and impaired driving ability. The risk and/or severity may be increased when combined with alcohol or other medications that can also cause sedation. Let your doctor know prior to receiving allopurinol if you are currently using alcohol or receiving treatment with pyrilamine, as you may be more likely to experience sedation-related side effects. Do not drive, operate machinery, or engage in potentially hazardous activities requiring mental alertness and motor coordination until the sedative effects have gone away and you know how these medications affect you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate:

allopurinol pheniramine

Applies to: allopurinol and Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Allopurinol may cause sedation, drowsiness, dizziness, and impaired driving ability. The risk and/or severity may be increased when combined with alcohol or other medications that can also cause sedation. Let your doctor know prior to receiving allopurinol if you are currently using alcohol or receiving treatment with pheniramine, as you may be more likely to experience sedation-related side effects. Do not drive, operate machinery, or engage in potentially hazardous activities requiring mental alertness and motor coordination until the sedative effects have gone away and you know how these medications affect you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate:

allopurinol phenyltoloxamine

Applies to: allopurinol and Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Allopurinol may cause sedation, drowsiness, dizziness, and impaired driving ability. The risk and/or severity may be increased when combined with alcohol or other medications that can also cause sedation. Let your doctor know prior to receiving allopurinol if you are currently using alcohol or receiving treatment with phenyltoloxamine, as you may be more likely to experience sedation-related side effects. Do not drive, operate machinery, or engage in potentially hazardous activities requiring mental alertness and motor coordination until the sedative effects have gone away and you know how these medications affect you. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate:

pyrilamine pheniramine

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine) and Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Using pyrilamine together with pheniramine may increase side effects such as drowsiness, blurred vision, dry mouth, heat intolerance, flushing, decreased sweating, difficulty urinating, abdominal cramping, constipation, irregular heartbeat, confusion, and memory problems. Side effects may be more likely to occur in the elderly or those with a debilitating condition. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. Talk to your doctor if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate:

pyrilamine phenyltoloxamine

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine) and Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Using pyrilamine together with phenyltoloxamine may increase side effects such as drowsiness, blurred vision, dry mouth, heat intolerance, flushing, decreased sweating, difficulty urinating, abdominal cramping, constipation, irregular heartbeat, confusion, and memory problems. Side effects may be more likely to occur in the elderly or those with a debilitating condition. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. Talk to your doctor if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Moderate:

pheniramine phenyltoloxamine

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine) and Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Using pheniramine together with phenyltoloxamine may increase side effects such as drowsiness, blurred vision, dry mouth, heat intolerance, flushing, decreased sweating, difficulty urinating, abdominal cramping, constipation, irregular heartbeat, confusion, and memory problems. Side effects may be more likely to occur in the elderly or those with a debilitating condition. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. Talk to your doctor if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Food/lifestyle interactions

Moderate food/lifestyle interactions

Moderate:

allopurinol Food/Lifestyle

Applies to: allopurinol

Allopurinol should generally be taken after a meal to reduce side effects. If your daily dose exceeds 300 mg, you may also ask your healthcare provider if it is okay to divide the total daily dose into smaller doses given more frequently instead of once a day, as this may also reduce stomach upset that can happen with allopurinol. It is best to avoid or limit the consumption of alcohol, as it can increase drowsiness or other nervous system side effects of allopurinol. You should also 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 medications without first talking to your doctor.

Moderate:

phenylpropanolamine Food/Lifestyle

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Using phenylpropanolamine with alcohol can increase the risk of cardiovascular side effects such as increased heart rate, chest pain, or blood pressure changes. In addition, you may also be more likely to experience nervous system side effects such as dizziness, drowsiness, depression, and difficulty concentrating. You should avoid or limit the use of alcohol while being treated with phenylpropanolamine. Do not use more than the recommended dose of phenylpropanolamine, 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.

Moderate:

pyrilamine Food/Lifestyle

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

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

Moderate:

pheniramine Food/Lifestyle

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

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

Moderate:

phenyltoloxamine Food/Lifestyle

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

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

Moderate:

phenylpropanolamine Caffeine

Applies to: Poly-D (pheniramine / phenylpropanolamine / phenyltoloxamine / pyrilamine)

Both phenylpropanolamine and caffeine can increase blood pressure and heart rate, and combining them may enhance these effects. Talk to your doctor before using these medications, especially if you have a history of high blood pressure or heart disease. You may need a dose adjustment or more frequent monitoring by your doctor to safely use both medications. Contact your doctor if your condition changes or you experience increased side effects. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.

Disease interactions

29 potential interactions Applies to: 21 conditions, including Depression, Asthma, Benign Prostatic Hyperplasia, COPD, and Diarrhea.

Asthma

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Benign Prostatic Hyperplasia

Moderate:

Poly-D

The phenylpropanolamine in Poly-D 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.

Bone Marrow Depression/Low Blood Counts

Moderate:

allopurinol

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

Bone marrow suppression has been reported in patients receiving allopurinol; however, most of these patients were receiving concomitant medications with the known potential to cause such an effect. The suppression has occurred from as early as 6 weeks to as long as 6 years after the initiation of allopurinol therapy. Therapy with allopurinol should be administered cautiously to patients with or predisposed to bone marrow suppression.

Cardiovascular Conditions and Disorders

Major:

Poly-D

The phenylpropanolamine in Poly-D 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.

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Cerebrovascular Insufficiency

Major:

Poly-D

The phenylpropanolamine in Poly-D 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.

COPD

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Dehydration

Moderate:

allopurinol

Allopurinol has a moderate potential interaction with Dehydration.

Patients with pre-existing kidney conditions, including chronic kidney disease or a history of kidney stones, may be at increased risk for worsening of kidney function or acute kidney injury due to xanthine calculi during treatment with this drug. Ensure adequate hydration to maintain a daily urine output of at least 2 liters in adults and 2 liters/m2/day (or 100 mL/m2/hour) in pediatric patients. Maintaining a neutral to slightly alkaline urine pH is also recommended to prevent xanthine calculi and reduce urate precipitation. Renal function should be closely monitored, especially during the early stages of therapy.

Depression

Major:

Poly-D

The pyrilamine in Poly-D 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.

Diabetes Mellitus

Moderate:

Poly-D

The phenylpropanolamine in Poly-D 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.

Diarrhea

Moderate:

allopurinol

Allopurinol has a moderate potential interaction with Diarrhea.

Patients with pre-existing kidney conditions, including chronic kidney disease or a history of kidney stones, may be at increased risk for worsening of kidney function or acute kidney injury due to xanthine calculi during treatment with this drug. Ensure adequate hydration to maintain a daily urine output of at least 2 liters in adults and 2 liters/m2/day (or 100 mL/m2/hour) in pediatric patients. Maintaining a neutral to slightly alkaline urine pH is also recommended to prevent xanthine calculi and reduce urate precipitation. Renal function should be closely monitored, especially during the early stages of therapy.

Gastrointestinal Obstruction

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Glaucoma/Intraocular Hypertension

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Moderate:

Poly-D

The phenylpropanolamine in Poly-D 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.

Moderate:

Poly-D

The pyrilamine in Poly-D 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.

Hyperthyroidism

Major:

Poly-D

The phenylpropanolamine in Poly-D 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.

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Hypotension

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Liver Disease

Moderate:

allopurinol

Allopurinol has a moderate potential interaction with Liver Disease.

Allopurinol may cause hepatotoxicity. In patients with pre-existing liver disease, monitor liver enzymes periodically during the early stages of therapy. Discontinue treatment in patients with elevated liver enzymes.

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Moderate:

Poly-D

The pyrilamine in Poly-D 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.

Prostate Tumor, Benign

Moderate:

Poly-D

The phenylpropanolamine in Poly-D 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.

Psychiatric Disorders

Moderate:

Poly-D

The phenylpropanolamine in Poly-D has a moderate potential interaction with Psychiatric Disorders.

Phenylpropanolamine may precipitate or exacerbate psychotic symptoms, particularly at high dosages. Therapy with phenylpropanolamine should be administered cautiously in patients with a history of psychiatric disorders.

Psychosis

Moderate:

Poly-D

The phenylpropanolamine in Poly-D has a moderate potential interaction with Psychosis.

Phenylpropanolamine may precipitate or exacerbate psychotic symptoms, particularly at high dosages. Therapy with phenylpropanolamine should be administered cautiously in patients with a history of psychiatric disorders.

Renal Dysfunction

Moderate:

allopurinol

Allopurinol has a moderate potential interaction with Renal Dysfunction.

Allopurinol and its primary active metabolite, oxipurinol, are eliminated by the kidneys, and any changes in renal function will likely increase exposure. Additionally, treatment with allopurinol may result in renal impairment due to formation of xanthine calculi or due to precipitation of urates in patients receiving concomitant uricosuric agents. Patients with pre-existing renal disease, may be at increased risk for worsening renal impairment due to xanthine calculi or precipitation of urates while receiving treatment. These patients require lower dosages of allopurinol than normal to control serum urate levels and close monitoring of laboratory parameters of renal function to reassess the patient's dosage. Treatment with allopurinol tablets has not been studied in pediatric patients with severe renal impairment (eGFR less than 20 mL/min) or on dialysis.

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Urinary Retention

Moderate:

Poly-D

The pheniramine, phenyltoloxamine and pyrilamine in Poly-D all have 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.

Moderate:

Poly-D

The pyrilamine in Poly-D 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.

Vomiting

Moderate:

allopurinol

Allopurinol has a moderate potential interaction with Vomiting.

Patients with pre-existing kidney conditions, including chronic kidney disease or a history of kidney stones, may be at increased risk for worsening of kidney function or acute kidney injury due to xanthine calculi during treatment with this drug. Ensure adequate hydration to maintain a daily urine output of at least 2 liters in adults and 2 liters/m2/day (or 100 mL/m2/hour) in pediatric patients. Maintaining a neutral to slightly alkaline urine pH is also recommended to prevent xanthine calculi and reduce urate precipitation. Renal function should be closely monitored, especially during the early stages of therapy.

More resources

allopurinol

A total of 452 drugs are known to interact with allopurinol.

Poly-D

A total of 568 drugs are known to interact with Poly-D.

Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.