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Generic name: tobramycin

What is Bethkis?

Bethkis is a prescription medicine that is used to treat people with cystic fibrosis who have a bacterial infection called Pseudomonas aeruginosa. Bethkis contains an antibacterial medicine called tobramycin (an aminoglycoside).

It is not known if Bethkis is safe and effective:

  • in children under 6 years of age
  • in people who have decreased lung volume or a forced expiratory volume in one second (FEV1) less than 40% or greater than 80% predicted
  • in people who are colonized with a bacterium called Burkholderia cepacian

What is Psuedomonas aeriguinosa?

It is a very common bacterium that infects the lungs of nearly everyone with cystic fibrosis at some time during their lives. Some people do not get this infection until later in their lives, while others get it very young. It is one of the most damaging bacteria for people with cystic fibrosis. If the infection is not properly managed, it will continue to damage your lungs causing further problems to your breathing.

Who should not take Bethkis?

Do not take Bethkis if you are allergic to tobramycin, any of the ingredients in Bethkis, or to any other aminoglycoside antibacterial.

See the end of this Patient Information for a complete list of ingredients in Bethkis.

What should I tell my healthcare provider before taking Bethkis?

Before you take Bethkis, tell your healthcare provider about all of your medical conditions, including if you:

  • have or have had hearing problems (including noises in your ears such as ringing or hissing)
  • have dizziness
  • have or have had kidney problems
  • have or have had problems with muscle weakness such as myasthenia gravis or Parkinson’s disease
  • have or have had breathing problems such as wheezing, coughing, or chest tightness
  • are pregnant or plan to become pregnant. Bethkis is in a class of medicines that can harm your unborn baby and may be connected with complete deafness in babies at birth. The deafness affects both ears and cannot be changed.
  • are breastfeeding or plan to breastfeed. It is not known if Bethkis passes into your breast milk. Tobramycin, the medicine in Bethkis may cause the following symptoms in your breastfed baby:
    • loose or bloody stools
    • yeast infection in the mouth or throat (thrush)
    • diaper rash

Call your baby’s healthcare provider if your breastfed baby has any of these problems. Talk to your healthcare provider about the best way to feed your baby during treatment with Bethkis.

  • are receiving aminoglycoside therapy by injection or through a vein (intravenous) while taking Bethkis. Your blood levels of tobramycin will be checked.

Tell your healthcare provider about all the medicines you take, including prescription medicines, over-the-counter medicines, vitamins, and herbal supplements.

How should I take Bethkis?

  • See the step-by-step Instructions for Use that comes with Bethkis.
  • Take Bethkis exactly as your healthcare provider tells you to. Do not change your dose or stop taking Bethkis unless your healthcare provider tells you to.
  • The usual dose of Bethkis for adults and children over 6 years of age is:
    • 1 single-use ampule of Bethkis inhaled 2 times each day using your hand-held PARI LC PLUS Reusable Nebulizer with a PARI Vios air compressor.
  • Each dose of Bethkis should be taken as close to 12 hours apart as possible.
  • You should not take your dose of Bethkis less than 6 hours apart.
  • Bethkis is taken as a breathing treatment (inhalation) with a hand-held PARI LC Reusable Nebulizer with a PARI Vios air compressor. Do not use any other nebulizer for your Bethkis treatment.
  • Do not mix or dilute Bethkis with dornase alfa or other medicines in your nebulizer system.
  • Each treatment of Bethkis should take about 15 minutes.
  • Bethkis should be inhaled while you are sitting or standing upright and breathing normally through the mouthpiece of the nebulizer. Nose clips may help you to breathe through your mouth.
  • If you forget to take Bethkis and there are at least 6 hours to your next dose, take your dose as soon as you can. Otherwise, wait for your next dose. Do not double the dose to make up for the missed dose.
  • After taking Bethkis for 28 days, you should stop taking it and wait 28 days. After you have stopped taking Bethkis for 28 days, you should start taking Bethkis again for 28 days. Complete the full 28-day course even if you are feeling better. It is important that you keep to the 28-day on, 28-day off cycle.

If you are taking several other medicines or treatments to treat your cystic fibrosis, you should take your medicines or other treatments before inhaling Bethkis or as directed by your healthcare provider.

Taking Bethkis with certain other medicines can cause serious side effects.

If you are taking Bethkis, you should discuss with your healthcare provider if you should take:

  • other medicines that may harm your nervous system, kidneys, or hearing
  • “water pills” (diuretics) such as ethacrynic acid, furosemide, or intravenous mannitol
  • Urea

Ask your healthcare provider or pharmacist for a list of these medicines, if you are not sure.

Know the medicines you take. Keep a list of them and show it to your healthcare provider and pharmacist when you get a new medicine.

  • If you take too much Bethkis, call your healthcare provider or go to the nearest hospital emergency room right away.

What are the possible side effects of Bethkis?

Bethkis can cause serious side effects, including:

  • hearing loss or ringing in the ears (ototoxicity). Some people who were treated with tobramycin, the medicine in Bethkis had hearing loss or ringing in the ears. Tell your healthcare provider right away if you have hearing loss or hear noises in your ears (such as ringing or hissing), or if you develop vertigo, dizziness, or difficulty with balance.
  • worsening kidney problems (nephrotoxicity). Your healthcare provider may do a blood test and urine test to check how your kidneys are working while you are taking Bethkis.
  • worsening muscle weakness (neuromuscular disorder). Bethkis can cause muscle weakness to get worse in people who already have problems with muscle weakness (myasthenia gravis or Parkinson’s disease).
  • severe breathing problems (bronchospasm). Tell your healthcare provider right away if you get any of these symptoms of bronchospasm while taking Bethkis:
    • shortness of breath with wheezing
    • coughing and chest tightness

The most common side effects of Bethkis include:

  • worsening of lung problems or cystic fibrosis
  • noisy breathing (rales)
  • abnormal red blood cell activity
  • changes in your voice (hoarseness)

These are not all of the possible side effects of Bethkis.

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

General information about the safe and effective use of Bethkis

Medicines are sometimes prescribed for purposes other than those listed in a Patient Information leaflet. Do not use Bethkis for a condition for which it was not prescribed. Do not give Bethkis to other people, even if they have the same symptoms that you have. It may harm them.

You can ask your pharmacist or healthcare provider for more information about Bethkis that is written for health professionals.

How should I store Bethkis?

Bethkis should be stored under refrigeration at 2°C ‑ 8°C (36°F ‑ 46°F). Upon removal from the refrigerator, or if refrigeration is unavailable, Bethkis pouches (opened or unopened) may be stored at room temperature [up to 25°C (77°F)] for up to 28 days. Bethkis should not be used beyond the expiration date stamped on the ampule when stored under refrigeration 2°C ‑ 8°C (36°F ‑ 46°F) or beyond 28 days when stored at room temperature [up to 25°C (77°F)].

Bethkis ampules should not be exposed to intense light. Bethkis is light sensitive; unopened ampules should be returned to the foil pouch. The solution in the ampule is colorless to pale yellow, but may darken with age if not stored in the refrigerator; however, the color change does not indicate any change in the quality of the product as long as it is stored within the recommended storage conditions.

What are the ingredients in Bethkis?

Active ingredient: tobramycin

Inactive ingredients: sodium chloride, sulfuric acid in water for injection, and sodium hydroxide (for pH adjustment)

For more information, go to or call 1-888-661-9260.

Source: National Library of Medicine. Last updated December 22, 2019.