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Can you take Grepafloxacin with Phenergan Fortis?

1 drug interaction and 37 additional warnings found for the following 2 drugs:

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Drug interactions

Major drug interactions

Major:

promethazine grepafloxacin

Applies to: Phenergan Fortis (promethazine) and grepafloxacin

Grepafloxacin is no longer on the market in the U.S. Do not take grepafloxacin with any other medication.

Food/lifestyle interactions

Moderate food/lifestyle interactions

Moderate:

promethazine Alcohol (Ethanol)

Applies to: Phenergan Fortis (promethazine)

Ask your doctor before using promethazine together with ethanol (alcohol). This can cause uncontrollable movements, agitation, seizures, severe dizziness or fainting, coma, very deep sleep, irregular heartbeats, and high or low body temperature. Use caution when driving, operating machinery, or performing other hazardous activities, these medicaions may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities. 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

36 potential interactions Applies to: 34 conditions, including High Blood Pressure, Asthma, Rheumatoid Arthritis, COPD, and Seizures.

Acute Alcohol Intoxication

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Acute Alcohol Intoxication.

Phenothiazines are contraindicated in the presence of large amounts of central nervous system depressants such as alcohol. The risk of suicide and the danger of overdose may be increased in patients who use alcohol excessively. Phenothiazines should be used with caution in patients experiencing alcohol withdrawal.

Alcoholism

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Alcoholism.

Phenothiazines are contraindicated in the presence of large amounts of central nervous system depressants such as alcohol. The risk of suicide and the danger of overdose may be increased in patients who use alcohol excessively. Phenothiazines should be used with caution in patients experiencing alcohol withdrawal.

Altered Consciousness

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Altered Consciousness.

The use of phenothiazines is contraindicated in comatose patients and patients with severe central nervous system depression. Phenothiazines may potentiate the CNS and respiratory depression in these patients.

Arrhythmia

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Arrhythmia.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Asthma

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis 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.

Bone Marrow Depression/Low Blood Counts

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Bone Marrow Depression/Low Blood Counts.

Phenothiazines may cause hematologic toxicity. In patients with preexisting blood dyscrasias, bone marrow suppression, or a history of drug-induced leukopenia or neutropenia, phenothiazines should not be used or are contraindicated. Complete blood counts should be regularly monitored in patients with risk factors for blood dyscrasias. If white blood cell counts indicate cellular depression, discontinue treatment and institute appropriate therapy.

Breast Cancer

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis has a moderate potential interaction with Breast Cancer.

The chronic use of phenothiazines is associated with persistent elevations in prolactin levels. The clinical significance in patients with a history of breast cancer is unknown and should be considered prior to therapy; approximately one-third of human breast cancers are thought to be prolactin-dependent. Chronic administration of neuroleptic drugs has been associated with mammary tumorigenesis in animal studies; however, evidence is inconclusive in humans.

Cardiovascular Conditions and Disorders

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Cardiovascular Conditions and Disorders.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Central Nervous System Disorders

Major:

grepafloxacin

Grepafloxacin has a major potential interaction with Central Nervous System Disorders.

Quinolones may cause CNS stimulation manifested as tremors, agitation, restlessness, anxiety, confusion, hallucinations, paranoia, insomnia, toxic psychosis, and/or seizures. Benign intracranial hypertension has also been reported. Therapy with quinolones should be administered cautiously in patients with or predisposed to seizures or other CNS abnormalities. In addition, these patients should be advised to avoid the consumption of caffeine-containing products during therapy with some quinolones, most notably ciprofloxacin, enoxacin, and cinoxacin, since these agents can substantially reduce the clearance of caffeine and other methylxanthines, potentially resulting in severe CNS reactions.

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis has a moderate potential interaction with Central Nervous System Disorders.

Phenothiazines can lower the seizure threshold. Caution is recommended during administration in patients with a history of convulsive disorders or EEG abnormalities. Anticonvulsant therapy should be maintained or adequately adjusted during phenothiazine treatment.

Cerebrovascular Insufficiency

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Cerebrovascular Insufficiency.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

COPD

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis 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.

Dehydration

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Dehydration.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Gastrointestinal Obstruction

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis 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.

Glaucoma/Intraocular Hypertension

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis 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.

High Blood Pressure

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with High Blood Pressure.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

History - Cerebrovascular Disease

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with History - Cerebrovascular Disease.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

History - Myocardial Infarction

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with History - Myocardial Infarction.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Hypocalcemia

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Hypocalcemia.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Hypotension

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Hypotension.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Liver Disease

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Liver Disease.

Therapy with phenothiazines should be administered cautiously or are contraindicated in patients with preexisting liver disease or with a history of jaundice due to phenothiazine hypersensitivity. Patients with a history of hepatic encephalopathy due to cirrhosis may have increased sensitivity to the central nervous system effects of some phenothiazines (e.g., chlorpromazine). Treatment should be discontinued if jaundice occurs.

Myasthenia Gravis

Major:

grepafloxacin

Grepafloxacin has a major potential interaction with Myasthenia Gravis.

Fluoroquinolones have neuromuscular blocking activity and may exacerbate muscle weakness in persons with myasthenia gravis. Postmarketing serious adverse events, including deaths and requirement for ventilatory support, have been associated with fluoroquinolones use in persons with myasthenia gravis. Fluoroquinolones should be avoided in patients with history of myasthenia gravis.

Neuroleptic Malignant Syndrome

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Neuroleptic Malignant Syndrome.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis has a moderate potential interaction with Neuroleptic Malignant Syndrome.

Therapy with phenothiazines may precipitate or aggravate a potentially fatal symptom complex known as neuroleptic malignant syndrome (NMS). Treatment should not be initiated in patients with active NMS, and should be immediately discontinued if currently administered in such patients. In patients with a history of NMS, introduction or reintroduction of phenothiazines should be carefully considered, since NMS may recur.

Organ Transplant

Major:

grepafloxacin

Grepafloxacin has a major potential interaction with Organ Transplant.

Tendonitis and ruptures of the shoulder, hand, and Achilles tendons have been reported in patients receiving quinolones, both during and after treatment. Avoid the use of these agents in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture. Therapy with quinolones should be administered cautiously in patients with patients with kidney, heart, and lung transplant, since it may delay the recognition or confound the diagnosis of a quinolone-induced musculoskeletal effect. Factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. It is recommended to discontinue these agents if, at any time during therapy, pain, inflammation or rupture of a tendon develops and institute appropriate treatment.

Parkinsonism

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis has a moderate potential interaction with Parkinsonism.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Peripheral Neuropathy

Major:

grepafloxacin

Grepafloxacin has a major potential interaction with Peripheral Neuropathy.

The use of quinolones has been associated with an increased risk of peripheral neuropathy. Monitor closely and discontinue their use in patients experiencing symptoms of peripheral neuropathy. It is recommended to avoid these agents in patients who have previously experienced peripheral neuropathy.

Pheochromocytoma

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Pheochromocytoma.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

Pulmonary Impairment

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Pulmonary Impairment.

Promethazine is contraindicated for use in the treatment of lower respiratory tract symptoms including asthma. Furthermore, promethazine tablets may lead to potentially fatal respiratory depression, and its use should be avoided in patients with compromised respiratory function such as patients with COPD, and sleep apnea.

Renal Dysfunction

Major:

grepafloxacin

Grepafloxacin has a major potential interaction with Renal Dysfunction.

Tendonitis and ruptures of the shoulder, hand, and Achilles tendons have been reported in patients receiving quinolones, both during and after treatment. Avoid the use of these agents in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture. Therapy with quinolones should be administered cautiously in patients with patients with kidney, heart, and lung transplant, since it may delay the recognition or confound the diagnosis of a quinolone-induced musculoskeletal effect. Factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. It is recommended to discontinue these agents if, at any time during therapy, pain, inflammation or rupture of a tendon develops and institute appropriate treatment.

Respiratory Arrest

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Respiratory Arrest.

The use of phenothiazines is contraindicated in comatose patients and patients with severe central nervous system depression. Phenothiazines may potentiate the CNS and respiratory depression in these patients.

Rheumatoid Arthritis

Major:

grepafloxacin

Grepafloxacin has a major potential interaction with Rheumatoid Arthritis.

Tendonitis and ruptures of the shoulder, hand, and Achilles tendons have been reported in patients receiving quinolones, both during and after treatment. Avoid the use of these agents in patients who have a history of tendon disorders or have experienced tendinitis or tendon rupture. Therapy with quinolones should be administered cautiously in patients with patients with kidney, heart, and lung transplant, since it may delay the recognition or confound the diagnosis of a quinolone-induced musculoskeletal effect. Factors that may independently increase the risk of tendon rupture include strenuous physical activity, renal failure, and previous tendon disorders such as rheumatoid arthritis. It is recommended to discontinue these agents if, at any time during therapy, pain, inflammation or rupture of a tendon develops and institute appropriate treatment.

Seizures

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis has a moderate potential interaction with Seizures.

Phenothiazines can lower the seizure threshold. Caution is recommended during administration in patients with a history of convulsive disorders or EEG abnormalities. Anticonvulsant therapy should be maintained or adequately adjusted during phenothiazine treatment.

Tardive Dyskinesia

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Tardive Dyskinesia.

Promethazine has weak central antidopaminergic activity. While its use is rarely associated with adverse effects secondary to dopaminergic blockade, large doses have produced extrapyramidal reactions. During chronic administration and/or high-dose therapy, the usual contraindications, warnings and precautions applicable to phenothiazines should be observed with promethazine.

Urinary Retention

Moderate:

Phenergan Fortis

The promethazine in Phenergan Fortis 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.

Valvular Heart Disease

Major:

Phenergan Fortis

The promethazine in Phenergan Fortis has a major potential interaction with Valvular Heart Disease.

Phenothiazines may cause hypotension. Patients with pheochromocytoma, cerebral vascular or renal insufficiency, cardiovascular disease, or a severe cardiac reserve deficiency (e.g., mitral insufficiency) may be more prone to hypotensive reactions. Close monitoring is recommended during treatment if used in at-risk patients; some products may be contraindicated (e.g., thioridazine). Large doses and parenteral administration should be used cautiously, or avoided, in patients with impaired cardiovascular systems.

More resources

grepafloxacin

A total of 672 drugs are known to interact with grepafloxacin.

Phenergan Fortis

A total of 714 drugs are known to interact with Phenergan Fortis.

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.