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Drug Profile

The information on this site is intended to supplement and enhance, not replace, the advice of a physician who is familiar with your medical history. Decisions about your health should always be made ONLY after detailed conversation with your doctor.

Generic drug name: tobramycin (TOE bra mye sin)
Brand name(s): TOBREX
GENERIC: available FAMILY: Infection
Find the drug label by searching at DailyMed.

Limited Use [what does this mean?]
Generic drug name: gentamicin (JEN ta mye sin)
Brand name(s): GARAMYCIN, GENOPTIC, GENTAK
GENERIC: available FAMILY: Antibiotics
Find the drug label by searching at DailyMed.

Pregnancy and Breast-feeding Warnings [top]

Pregnancy Warning

Gentamicin has been shown to depress both body and kidney weights and to harm kidney structure. Information is lacking for tobramycin. Use during pregnancy only for clear medical reasons. Tell your doctor if you are pregnant or thinking of becoming pregnant before you take these drugs.

Breast-feeding Warning

No information is available from either human or animal studies. Since it is likely that these drugs, like many others, are excreted in human milk, you should consult with your doctor if you are planning to nurse.

Facts About This Drug [top]

Gentamicin and tobramycin are used in ointment, cream or liquid form to treat eye, ear and skin infections. Drugs in this family (aminoglycosides) are also given intravenously in the hospital to treat serious infections, but the information on this page does not apply to this use.

Gentamicin is sometimes used on the skin to treat severe burns that are infected. This is not a recommended use. If you use gentamicin this way, you may develop bacteria that are resistant to the drug, and the...

Gentamicin and tobramycin are used in ointment, cream or liquid form to treat eye, ear and skin infections. Drugs in this family (aminoglycosides) are also given intravenously in the hospital to treat serious infections, but the information on this page does not apply to this use.

Gentamicin is sometimes used on the skin to treat severe burns that are infected. This is not a recommended use. If you use gentamicin this way, you may develop bacteria that are resistant to the drug, and the injected form of gentamicin might then be ineffective if you ever receive it.[1]

Topical tobramycin rarely has been associated with anaphylactic reactions (a severe allergic reaction) and severe skin reactions such as Stevens-Johnson syndrome (a potentially life-threatening blistering skin reaction disorder).[2] Topical gentamicin also has rarely been associated with severe allergic reactions.

Before You Use This Drug [top]

Tell your doctor if you have or have had:

  • allergy to gentamicin or tobramycin
  • an unusual reaction to any aminoglycoside (neomycin, for example)
  • pregnancy or are breast-feeding

Tell your doctor about any other drugs you take, including aspirin, herbs, vitamins, and other nonprescription products.

When You Use This Drug [top]

  • Call your doctor if your infection does not improve within a few days or if it gets worse.
  • Avoid wearing contact lenses during treatment.
  • Use all the gentamicin or tobramycin your doctor prescribed, even if you feel better before you finish. If you stop too soon, your symptoms could come back.

How to Use This Drug [top]

  • Follow the instructions for application of eye drops and ointments  so that you won’t absorb the drug into your body and possibly suffer serious adverse effects.
  • If you miss a dose, take it as soon as you remember, but skip it if it is almost time for the next dose. Do not take double doses.
  • Do not share your medication with others.
  • Take the drug at the same time(s) each day.
  • Store at room temperature with lid on tightly. Do not store in the bathroom. Do not expose to heat, moisture, or strong light. Keep out of reach of children.

Interactions with Other Drugs [top]

The following drugs, biologics (e.g., vaccines, therapeutic antibodies), or foods are listed in Evaluations of Drug Interactions 2003 as causing “highly clinically significant” or “clinically significant” interactions when used together with any of the drugs in this section. In some sections with multiple drugs, the interaction may have been reported for one but not all drugs in this section, but we include the interaction because the drugs in this section are similar to one another. We have also included potentially serious interactions listed in the drug’s FDA-approved professional package insert or in published medical journal articles. There may be other drugs, especially those in the families of drugs listed below, that also will react with this drug to cause severe adverse effects. Make sure to tell your doctor and pharmacist the drugs you are taking and tell them if you are taking any of these interacting drugs:

carbenicillin, cephalothin, cidofovir, GEOCILLIN, INDOCIN, indomethacin, tubocurarine, VISTIDE.

Adverse Effects [top]

Call your doctor immediately if you experience:

  • black, tarry stools
  • blood in urine or stools
  • eye pain, sensitivity to light, or tearing
  • itching, redness, swelling, or other irritation that has appeared since you started using the drug
  • seeing, hearing, or feeling things that are not there
  • unusual bleeding or bruising

Call your doctor if these symptoms continue:

  • burning or stinging of eyes

Signs of overdose:

  • increased eye watering
  • itching, redness, or swelling of the eyes or eyelids
  • painful irritation of the clear front part of eye

If you suspect an overdose, call this number to contact your poison control center: (800) 222-1222.

last reviewed January 31, 2021