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Drug Interaction Report

1 drug interaction and 20 additional warnings found for the following 2 drugs:

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Drug interactions

Moderate drug interactions

Moderate:

phenylpropanolamine acarbose

Applies to: G-Vent (guaifenesin / phenylpropanolamine), acarbose

Phenylpropanolamine may interfere with blood glucose control and reduce the effectiveness of acarbose and other diabetic medications.

Monitor your blood sugar levels closely. You may need a dose adjustment of your diabetic medications during and after treatment with phenylpropanolamine.

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:

Caffeine phenylpropanolamine

Applies to: G-Vent (guaifenesin / phenylpropanolamine)

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.

Moderate:

Food/Lifestyle phenylpropanolamine

Applies to: G-Vent (guaifenesin / phenylpropanolamine)

Using phenylpropanolamine with alcohol can increase the risk of cardiovascular side effects such as:

  • increased heart rate
  • chest pain
  • blood pressure changes

In addition, you may also be more likely to experience nervous system side effects such as:

  • dizziness
  • drowsiness
  • depression
  • 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:

Food/Lifestyle acarbose

Applies to: acarbose

Alcohol may affect blood glucose levels in patients with diabetes. Both hypoglycemia (low blood sugar) and hyperglycemia (high blood sugar) may occur, depending on how much and how often you drink.

You should avoid using alcohol if your diabetes is not well controlled or if you have:

  • high triglycerides
  • neuropathy (nerve damage)
  • pancreatitis

Moderate alcohol consumption generally does not affect blood glucose levels if your diabetes is under control. However, it may be best to limit alcohol intake to one drink daily for women and two drinks daily for men (1 drink = 5 oz wine, 12 oz beer, or 1.5 oz distilled spirits) in conjunction with your normal meal plan.

Avoid drinking alcohol on an empty stomach or following exercise, as it may increase the risk of hypoglycemia.

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

17 potential interactionsApplies to: 17 conditions, including Benign Prostatic Hyperplasia, Hyperthyroidism, Psychosis, Diabetes Mellitus, and Liver Disease.

Benign Prostatic Hyperplasia

Moderate:

G-Vent

The phenylpropanolamine in G-Vent 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.

Cardiovascular Conditions and Disorders

Major:

G-Vent

The phenylpropanolamine in G-Vent 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.

Cerebrovascular Insufficiency

Major:

G-Vent

The phenylpropanolamine in G-Vent 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.

Cirrhosis

Major:

acarbose

Acarbose has a major potential interaction with Cirrhosis.

The use of acarbose is contraindicated in patients with primary cirrhosis.

Colonic Ulceration

Major:

acarbose

Acarbose has a major potential interaction with Colonic Ulceration.

The use of alpha-glucosidase inhibitors is contraindicated in patients with inflammatory bowel disease, colonic ulceration, partial intestinal obstruction, or any chronic intestinal disease associated with marked disorders of digestion or absorption. Alpha-glucosidase inhibitors competitively inhibit enzymes involved in the digestion of carbohydrates. Increased gas formation in the intestines due to fermentation of the undigested carbohydrates can worsen or aggravate intestinal problems.

Diabetes Mellitus

Moderate:

G-Vent

The phenylpropanolamine in G-Vent 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.

Diabetic Ketoacidosis

Major:

acarbose

Acarbose has a major potential interaction with Diabetic Ketoacidosis.

The use of alpha-glucosidase inhibitors is contraindicated for the treatment of patients with diabetic ketoacidosis.

Glaucoma/Intraocular Hypertension

Moderate:

G-Vent

The phenylpropanolamine in G-Vent 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.

Hyperthyroidism

Major:

G-Vent

The phenylpropanolamine in G-Vent 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.

Intestinal Obstruction

Major:

acarbose

Acarbose has a major potential interaction with Intestinal Obstruction.

The use of alpha-glucosidase inhibitors is contraindicated in patients with inflammatory bowel disease, colonic ulceration, partial intestinal obstruction, or any chronic intestinal disease associated with marked disorders of digestion or absorption. Alpha-glucosidase inhibitors competitively inhibit enzymes involved in the digestion of carbohydrates. Increased gas formation in the intestines due to fermentation of the undigested carbohydrates can worsen or aggravate intestinal problems.

Liver Disease

Moderate:

acarbose

Acarbose has a moderate potential interaction with Liver Disease.

The use of acarbose has been associated with dose-related elevations in serum transaminase levels and, rarely, hyperbilirubinemia and jaundice. Hepatic adverse effects may be more likely to occur at dosages exceeding 50 mg three times a day. Therapy with acarbose should be administered cautiously in patients with liver disease. Monitoring of serum transaminases is recommended every 3 months during the first year of treatment and periodically thereafter. If hepatotoxicity is suspected at any time, a dosage reduction or withdrawal of therapy may be indicated.

Malabsorption Syndrome

Major:

acarbose

Acarbose has a major potential interaction with Malabsorption Syndrome.

The use of alpha-glucosidase inhibitors is contraindicated in patients with inflammatory bowel disease, colonic ulceration, partial intestinal obstruction, or any chronic intestinal disease associated with marked disorders of digestion or absorption. Alpha-glucosidase inhibitors competitively inhibit enzymes involved in the digestion of carbohydrates. Increased gas formation in the intestines due to fermentation of the undigested carbohydrates can worsen or aggravate intestinal problems.

Noninfectious Colitis

Major:

acarbose

Acarbose has a major potential interaction with Noninfectious Colitis.

The use of alpha-glucosidase inhibitors is contraindicated in patients with inflammatory bowel disease, colonic ulceration, partial intestinal obstruction, or any chronic intestinal disease associated with marked disorders of digestion or absorption. Alpha-glucosidase inhibitors competitively inhibit enzymes involved in the digestion of carbohydrates. Increased gas formation in the intestines due to fermentation of the undigested carbohydrates can worsen or aggravate intestinal problems.

Prostate Tumor, Benign

Moderate:

G-Vent

The phenylpropanolamine in G-Vent 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:

G-Vent

The phenylpropanolamine in G-Vent 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:

G-Vent

The phenylpropanolamine in G-Vent 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

Major:

acarbose

Acarbose has a major potential interaction with Renal Dysfunction.

Acarbose may accumulate in patients with renal impairment. Following oral administration, 35% of a dose is recovered in the urine as either the parent drug or metabolites. However, long-term clinical trials in diabetic patients with significant renal dysfunction (serum creatinine > 2.0 mg/dL) have not been conducted. Therapy with acarbose should be administered cautiously in patients with renal dysfunction. The manufacturer does not recommend its use in patients with significantly impaired renal function.

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.

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Further information

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