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Penetrex Side Effects

Generic name: enoxacin

Note: This document contains side effect information about enoxacin. Some dosage forms listed on this page may not apply to the brand name Penetrex.

Applies to enoxacin: oral tablet.


Take all of the enoxacin that has been prescribed for you even if you begin to feel better. Your symptoms may start to improve before the infection is completely treated.

Drink plenty of extra fluids every day while taking enoxacin.

Take enoxacin on an empty stomach 1 hour before or 2 hours after meals.

Do not take antacids that contain magnesium or aluminum (e.g., Tums or Rolaids), the ulcer medicine sucralfate (Carafate), or vitamin or mineral supplements that contain iron or zinc for a minimum of 8 hours before or 2 hours after a dose of enoxacin. Taking antacids, sucralfate, or vitamin or mineral supplements too close to a dose of enoxacin can greatly decrease the effects of the antibiotic.

If you experience any of the following serious side effects, stop taking enoxacin (the active ingredient contained in Penetrex) and seek emergency medical attention or contact your doctor immediately:

If you experience any of the following less serious side effects, continue taking enoxacin and talk to your doctor:

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

For Healthcare Professionals

Applies to enoxacin: oral tablet.


Enoxacin (the active ingredient contained in Penetrex) therapy is generally well tolerated, and adverse effects are mild in nature. Discontinuation of therapy due to adverse effects occurs in approximately 3% of patients.[Ref]


Gastrointestinal disturbances due to enoxacin (the active ingredient contained in Penetrex) therapy may occur in up to 9% of patients. This most frequently includes nausea, abdominal pain, anorexia, dyspepsia, and diarrhea. Enoxacin therapy has resulted in pseudomembranous colitis although it has minimal effect on the anaerobic flora of the GI tract.[Ref]

Nervous system

Nervous system adverse effects occur in approximately 2% to 3% of patients. These most commonly include headache, dizziness, fatigue, nervousness, agitation, and insomnia. Seizures have also been reported in susceptible patients.[Ref]


Hypersensitivity reactions resulting in rash and pruritus have been reported in up to 1% of patients treated with enoxacin (the active ingredient contained in Penetrex) Photosensitivity can occur. Erythema multiforme, toxic epidermal necrolysis, and Stevens-Johnson Syndrome have also been reported.[Ref]


Asymptomatic elevations in hepatic transaminases have been reported in less than 1% of patients treated with enoxacin (the active ingredient contained in Penetrex) Cholestatic jaundice has been reported in one patient shortly after enoxacin administration.[Ref]


Hematologic abnormalities such as eosinophilia and leukopenia occur in less than 1% of enoxacin-treated patients.[Ref]


Arthralgias and myalgias occur rarely.[Ref]


Tachycardia and facial flushing have been reported rarely.[Ref]


Women treated with enoxacin (the active ingredient contained in Penetrex) may experience vaginal pruritus and vaginitis.[Ref]


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3. Bailey RR, Walker RJ, Lynn KL, et al. (1988) "Intravenous enoxacin for the treatment of pylenephritis: pharmacokinetic and clinical study." Br J Clin Pharmacol, 25, p. 223-8

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5. Foot M, Williams G, Want S, et al. (1988) "An open study of the safety and efficacy of enoxacin in complicated urinary tract infections." J Antimicrob Chemother, 21, p. 97-103

6. Naber KG, Sorgel F, Gutzler F, Bartosik-Wich B (1985) "In vitro activity, pharmacokinetics, clinical safety and therapeutic efficacy of enoxacin in the treatment of patients with complicated urinary tract infections." Infection, 23, p. 219-24

7. Edlund C, Lidbeck A, Kager L, Nord CE (1987) "Comparative effects of enoxacin and norfloxacin on human colonic microflora." Antimicrob Agents Chemother, 31, p. 1846-8

8. Edlund C, Lidbeck A, Kager L, Nord CE (1987) "Effect of enoxacin on colonic microflora of healthy volunteers." Eur J Clin Microbiol, 6, p. 298-300

9. Tsuei SE, Darragh AS, Brick I (1984) "Pharmacokinetics and tolerance of enoxacin in healthy volunteers administered at a dosage of 400 mg twice daily for 14 days." J Antimicrob Chemother, 14, p. 71-4

10. (2002) "Product Information. Penetrex (enoxacin)." Rhone Poulenc Rorer

11. Just PM (1993) "Overview of the fluoroquinolone antibiotics." Pharmacotherapy, 13, s4-17

12. Kawabe Y, Mizuno N, Sakakibara S (1989) "Photoallergic reaction caused by enoxacin." Photodermatol, 6, p. 58-60

13. Petri H, Tronnier H (1986) "Efficacy of enoxacin in the treatment of bacterial infections of the skin with regards to photosensitization." Infection, 14, s213-16

14. Kang JS, Kim TH, Park KB, Chung BH, Youn JI (1993) "Enoxacin photosensitivity." Photodermatol Photoimmunol Photomed, 9, p. 159-61

15. Amitrano L, Gigliotti T, Guardascione MA, Ascione A (1993) "Acute cholestatic liver injury induced by enoxacin." J Hepatol, 18, p. 139-40

Further information

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

Some side effects may not be reported. You may report them to the FDA.