Last updated on RxList: 12/8/2004
Penetrex Side Effects Center

Last reviewed on RxList 1/31/2016

Penetrex (enoxacin) is an antibiotic used to treat various bacterial infections, such as gonorrhea and urinary tract infections. The brand name Penetrex is discontinued, but generic versions may be available. Common side effects of Penetrex (enoxacin) include nausea, vomiting, dizziness, spinning sensation (vertigo), diarrhea, headache, lightheadedness, drowsiness, ringing in your ears, abdominal pain, insomnia, indigestion, rash, nervousness, anxiety, unusual taste in the mouth, itching, or increased sensitivity of the skin to sunlight.

Dosage of Penetrex depends on the infection being treated. Penetrex may interact with antacids containing magnesium or aluminum, sucralfate, vitamin or mineral supplements containing iron or zinc, bismuth subsalicylate (Pepto-Bismol), theophylline, digoxin, warfarin, probenecid, insulin or oral diabetes medications, nonsteroidal anti-inflammatory drugs (NSAIDs), or cyclosporine. Tell your doctor all medications and supplements you use. It is unknown if Penetrex will be harmful to a fetus. Tell your doctor if you are pregnant or could become pregnant during treatment. It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

Our Penetrex (enoxacin) Side Effects Drug Center provides a comprehensive view of available drug information on the potential side effects when taking this medication.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.


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Single-Dose Studies

During clinical trials, approximately 9% of patients treated with a single dose of 400 mg of enoxacin for uncomplicated urethral or endocervical gonorrhea reported adverse events.

The most frequently reported events in single-dose trials, without regard to drug relationship, were nausea and vomiting (2%). Events that occurred in less than 1% of patients are listed below.

CENTRAL NERVOUS SYSTEM:  headache, dizziness, somnolence; GASTROINTESTINAL: abdominal pain; GYNECOLOGIC: vaginal moniliasis; SKIN/HYPERSENSITIVITY: rash; LABORATORY ABNORMALITIES: increased AST (SGOT), decreased hemoglobin, decreased hematocrit, eosinophilia, leukocytosis, leukopenia, thrombocytosis, increased urinary protein, increased alkaline phosphatase, increased ALT (SGPT), increased bilirubin, hyperkalemia.

Multiple-Dose Studies

The incidence of adverse events reported by patients in multiple-dose clinical trials, without regard to drug relationship, was 23%. The incidence of drug-related adverse reactions in multiple-dose clinical trials was 16%. Among patients receiving multiple-dose therapy, enoxacin was discontinued because of an adverse event in 3.8% of patients.

The following events were considered likely to be drug-related in patients receiving multiple doses of enoxacin in clinical trials: nausea and/or vomiting 6%, dizziness 2%, headache 1%, abdominal pain 1%, diarrhea 1%, dyspepsia 1%.

The most frequently reported events in all multiple-dose clinical trials, without regard to drug relationship, were as follows: nausea and/or vomiting 8%, dizziness and/or vertigo 3%, headache 2%, diarrhea 2%, abdominal pain 2%, insomnia 1%, dyspepsia 1%, rash 1%, nervousness and/or anxiety 1%, unusual taste 1%, pruritus 1%.

Additional events that occurred in less than 1% of patients but >0.1% of patients are listed below.

BODY AS A WHOLE:  asthenia, fatigue, fever, malaise, back pain, chest pain, edema, chills; GASTROINTESTINAL: flatulence, constipation, dry mouth/throat, stomatitis, anorexia, gastritis, bloody stools; CENTRAL NERVOUS SYSTEM: somnolence, tremor, convulsions, paresthesia, confusion, agitation, depression, syncope, myoclonus, depersonalization, hypertonia; SKIN/HYPERSENSITIVITY: photosensitivity reaction, urticaria, hyperhidrosis, mycotic infection, erythema multiforme, toxic epidermal necrolysis, Stevens-Johnson syndrome; SPECIAL SENSES: tinnitus, conjunctivitis, visual disturbances including amblyopia; MUSCULOSKELETAL: myalgia, arthralgia; CARDIOVASCULAR: palpitations, tachycardia, vasodilation; RESPIRATORY: dyspnea, cough, epistaxis; HEMIC AND LYMPHATIC: purpura; UROGENITAL: vaginal moniliasis, vaginitis, urinary incontinence, renal failure.

The following adverse events occurred in less than 0.1% of patients in multiple-dose clinical trials but were considered significant: pseudomembranous colitis, hyperkinesia, amnesia, ataxia, hypotonia, psychosis, emotional lability, hallucination, schizophrenic reaction.

LABORATORY CHANGES: The following laboratory abnormalities appeared in ≥1.0% of patients receiving multiple doses of enoxacin: elevated AST (SGOT), elevated ALT (SGPT). It is not known whether these abnormalities were caused by the drug or the underlying conditions.

Worldwide Post-Marketing Experience

The most frequent spontaneously-reported adverse events in the worldwide post-marketing experience with multiple- and single-dose enoxacin use have been rashes, seizures/convulsions, and photosensitivity reactions; however, there is no evidence that the incidences of these events were larger than those observed in the clinical trials population.

Quinolone-class adverse reactions:   Although not reported in completed clinical studies with enoxacin, a variety of adverse events have been reported with other quinolones.

Clinical adverse events include:  erythema nodosum, hepatic necrosis, possible exacerbation of myasthenia gravis, nystagmus, intestinal perforation, hyperpigmentation, interstitial nephritis, polyuria, urinary retention, renal calculi, cardiopulmonary arrest, cerebral thrombosis, and laryngeal or pulmonary edema.

Laboratory adverse events include:  agranulocytosis, elevation of serum triglycerides and/or serum cholesterol, prolongation of the prothrombin time, candiduria, and crystalluria.


Read the entire FDA prescribing information for Penetrex (Enoxacin)


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© Penetrex Patient Information is supplied by Cerner Multum, Inc. and Penetrex Consumer information is supplied by First Databank, Inc., used under license and subject to their respective copyrights.

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