Medical Editor: John P. Cunha, DO, FACOEP Last updated on RxList: 2/9/2022
Tobi Side Effects Center

What Is Tobi?

Tobi (tobramycin) is an antibiotic used to treat lung infections in patients with cystic fibrosis.

What Are Side Effects of Tobi?

Common side effects of Tobi include:

  • hoarseness,
  • changes in voice, or
  • an unpleasant taste or odor of the medication.

Tell your doctor if you have unlikely but serious side effects of Tobi include:

  • signs of hearing damage (such as ringing or roaring sounds in the ears, hearing loss, dizziness), or
  • an unusual decrease in the amount of urine.

Dosage for Tobi

The recommended dosage of Tobi for adults and pediatric patients 6 years of age and older is 1 single-use ampule (300 mg) administered twice daily for 28 days. Doses should be taken 12 hours apart; they should not be taken less than 6 hours apart.

What Drugs, Substances, or Supplements Interact with Tobi?

Tobi may interact with urosemide, ethacryinc acid, or mannitol. Do not mix Tobi with dornase alfa in the nebulizer. Tell your doctor all prescription or over-the-counter medicines and supplements you use.

Tobi During Pregnancy or Breastfeeding

Tobi is not recommended for use during pregnancy. Although there have been reports of harm in babies born to women using similar drugs, the risk for harm may not be the same with this drug. Consult your doctor. It is unknown if inhaled tobramycin passes into breast milk. However, other forms of this drug pass into breast milk in very small amounts, and many doctors consider breastfeeding safe while using this drug. Consult your doctor before breastfeeding.

Additional Information

Our Tobi (tobramycin) 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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Tobi Consumer Information

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • new or worsening breathing problems, such as wheezing, cough, chest tightness, or trouble breathing;
  • hearing problems, ringing in your ears;
  • hoarse voice;
  • severe dizziness, spinning sensation, balance problems;
  • weak or shallow breathing;
  • muscle weakness; or
  • kidney problems--little or no urination, swelling in your feet or ankles, feeling tired or short of breath.

Common side effects may include:

  • cough, sore throat, hoarse voice;
  • feeling short of breath;
  • noisy breathing;
  • worsening of lung problems or cystic fibrosis;
  • coughing up mucus or blood;
  • altered sense of taste;
  • fever;
  • headache; or
  • rash.

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.

Read the entire detailed patient monograph for Tobi (Tobramycin)


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Tobi Professional Information


TOBI was generally well tolerated during two clinical studies in 258 cystic fibrosis patients ranging in age from 6 to 48 years. Patients received TOBI in alternating periods of 28 days on and 28 days off drug in addition to their standard cystic fibrosis therapy for a total of 24 weeks.

Voice alteration and tinnitus were the only adverse experiences reported by significantly more TOBI-treated patients. Thirty-three patients (13%) treated with TOBI complained of voice alteration compared to 17 (7%) placebo patients. Voice alteration was more common in the on-drug periods.

Eight patients from the TOBI group (3%) reported tinnitus compared to no placebo patients. All episodes were transient, resolved without discontinuation of the TOBI treatment regimen, and were not associated with loss of hearing in audiograms. Tinnitus is one of the sentinel symptoms of cochlear toxicity, and patients with this symptom should be carefully monitored for high frequency hearing loss. The numbers of patients reporting vestibular adverse experiences such as dizziness were similar in the TOBI and placebo groups.

Nine (3%) patients in the TOBI group and nine (3%) patients in the placebo group had increases in serum creatinine of at least 50% over baseline. In all nine patients in the TOBI group, creatinine decreased at the next visit.

Table 1 lists the percent of patients with treatment-emergent adverse experiences (spontaneously reported and solicited) that occurred in > 5% of TOBI patients during the two Phase III studies.

Table 1: Percent of Patients With Treatment Emergent Adverse Experiences Occurring in > 5% of TOBI Patients

Adverse Event TOBI
(n=258) %
(n=262) %
Cough Increased 46.1 47.3
Pharyngitis 38.0 39.3
Sputum Increased 37.6 39.7
Asthenia 35.7 39.3
Rhinitis 34.5 33.6
Dyspnea 33.7 38.5
Fever1 32.9 43.5
Lung Disorder 31.4 31.3
Headache 26.7 32.1
Chest Pain 26.0 29.8
Sputum Discoloration 21.3 19.8
Hemoptysis 19.4 23.7
Anorexia 18.6 27.9
Lung Function Decreased2 16.3 15.3
Asthma 15.9 20.2
Vomiting 14.0 22.1
Abdominal Pain 12.8 23.7
Voice Alteration 12.8 6.5
Nausea 11.2 16.0
Weight Loss 10.1 15.3
Pain 8.1 12.6
Sinusitis 8.1 9.2
Ear Pain 7.4 8.8
Back Pain 7.0 8.0
Epistaxis 7.0 6.5
Taste Perversion 6.6 6.9
Diarrhea 6.2 10.3
Malaise 6.2 5.3
Lower Respiratory Tract Infection 5.8 8.0
Dizziness 5.8 7.6
Hyperventilation 5.4 9.9
Rash 5.4 6.1
1Includes subjective complaints of fever.
2Includes reported decreases in pulmonary function tests or decreased lung volume on chest radiograph associated with intercurrent illness or study drug administration.

Adverse drug reactions ( < 5%) occurring more frequently with TOBI in the placebo-controlled studies and assessed as drug-related in ≥ 1% of patients:

Ear and Labyrinth Disorders

Tinnitus (3.1%, vs 0% for placebo)

Musculoskeletal and Connective Tissue Disorders

Myalgia (4.7%, vs 2.7% for placebo)

Infections and Infestations

Laryngitis (4.3%, vs 3.1% for placebo)

Adverse Drug Reactions Derived From Spontaneous Reports

The following adverse reactions have been identified during postapproval use of TOBI. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Ear and Labyrinth Disorders

Hearing loss (see WARNINGSOtotoxicity)

Skin and Subcutaneous TissueDiisorders

Hypersensitivity, pruritus, urticaria, rash

Nervous System Disorders

Aphonia, dysgeusia

Respiratory, Thoracic, and Mediastinal Disorders

Bronchospasm (see WARNINGSBronchospasm), oropharyngeal pain

Metabolism and Nutrition Disorders

Decreased appetite

Read the entire FDA prescribing information for Tobi (Tobramycin)

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

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