Healthy Living

Antibiotics for Cystic Fibrosis

Antibiotics for Cystic Fibrosis

Cystic fibrosis damages the lungs, digestive system, and other organs in the body. It affects the cells producing mucus, sweat, and digestive juices. It is caused due to defect in a gene. This gene changes a protein responsible for movement of salts in and out of cells. As a result, thick, sticky mucus gets accumulated in the respiratory system.

Antibiotics are used not only to treat but also to prevent lung infections. Antibiotics are used for a number of infections. However, they are ineffective against viruses. A broad-spectrum antibiotic is used to treat many infections whereas a narrow one is effective against only a few strains of bacteria.


Gentamicin is an antibiotic used to treat bacterial infections. It is used in patients with cystic fibrosis and other diseases. Cystic fibrosis is characterized by the formation and accumulation of sticky mucus in the lungs. Hence, patients experience breathing difficulty. Additionally, there is also an abnormal functioning of the lungs and pancreas. To combat this, patients are prescribed gentamicin.

Gentamicin was introduced to the U.S. in 1982, after the pharmaceutical company “Kalapharm” received FDA clearance for the drug. Gentamicin is part of a class of medications called aminoglycoside antibiotics. It is helpful for patients not only with cystic fibrosis but also several other bacterial infections, including meningitis and infection of the abdomen, bones, skin, lungs, joints, and urinary tract.

Gentamicin is administered as a liquid through an IV catheter directly into the blood. The risk of side effects from gentamicin is high. Severe kidney problems have been known to occur in some patients taking gentamicin, especially individuals who are dehydrated or elderly patients. Other side effects of gentamicin include:

Patients should be aware of these symptoms or side-effects. Contact a physician immediately if you begin to experience:


Ciprofloxacin is an antibiotic. It belongs to the class of medications known as fluoroquinolones. It is used to treat lung infections caused by specific bacteria. This medicine works by reducing the amount of bacteria present in the lungs. Ciprofloxacin is ineffective against viral infections. Overuse or unnecessary use will affect its effectiveness. This medicine is available in the form of tablets. For an adult, the usual dose with CF is 750mg to be taken twice a day in a month. One can take this antibiotic on an empty stomach or with food.

Patients may or may not experience side effects. Side effects commonly last only a couple of days; however, if these side effects become severe, it is important to inform your doctor. The side effects of ciprofloxacin include:

Less common side effects include:

  • Rash
  • Hives
  • Breathing difficulty
  • Numbness
  • Tingling
  • Yellowing of skin or eyes

In rare cases, it can lead to a severe intestinal condition. This condition may occur weeks or months after the treatment has stopped. It can also interact with certain medicines. Hence, medicines such as antacids, calcium, and products containing iron should not be taken along with ciprofloxacin. This antibiotic should be taken two hours before or 6 hours after taking those medicines. Prolonged use of this medication may cause oral thrush or a yeast infection.


Azithromycin is used to treat certain bacterial infections. It kills the bacteria and stops it from multiplying; thus, treating the infection. It is prescribed by a doctor and is available in:

  • Oral tablet form 
  • Oral suspension form
  • Extended-release oral suspension
  • Intravenous form

Oral tablets may cause side effects such as:

These side effects may cease within a few days or weeks; however, they may also become severe. One of the more serious side effects of azithromycin is liver problems, which would cause the following symptoms:

  • Tiredness
  • Loss of appetite
  • Dark urine
  • Yellowing of skin or whites of eyes
  • Stomach pain.

Azithromycin can also cause allergic reactions. The symptoms of an allergic reaction include:

  • Breathing problems
  • Hives
  • Stevens-Johnson syndrome
  • Toxic epidermal necrolysis
  • Swelling of face, lips, throat, or tongue.

In newborns, it may cause infantile hypertrophic pyloric stenosis. This medication should be taken as prescribed by the doctor. Zmax, which is in the form of an extended release liquid, is an oral suspension and should be consumed on an empty stomach an hour before the intake of a meal or two hours after consuming food. Drugs such as nelfinavir, warfarin, Coumadin, Jantoven, or other prescription and over-the counter medicines may interact with this antibiotic.


Aztreonam is an antibiotic used to fight severe or life-threatening bacterial infections. Aztreonam inhalation is used in cystic fibrosis patients with lung infections. It improves breathing symptoms. It is a monobactam antibiotic. This antibiotic works by ceasing the growth of bacteria. Aztreonam should not be taken in larger or smaller amounts. The medication is injected directly into the vein or muscle. The dosage would depend on the medical condition of the individual and the body’s response to the therapy. Side effects include:

Contact a doctor immediately if you begin to experience any of the following symptoms:


Meropenem is an antibiotic used to treat infections that are caused by bacteria. It is a broad-spectrum antibiotic and is active against gram-positive and gram–negative bacteria. It penetrates the bacterial cells and interferes with the synthesis of its vital cell wall components. This leads to cell death. It is injected into a vein through an IV. Meropenem is usually given every 8 hours. All directions should be followed on prescription label. Some common side effects include:

  • Mild diarrhea
  • Nausea
  • Vomiting
  • Mild skin rash
  • Headache

Severe Side effects include:

  • Diarrhea
  • Seizures
  • Pale skin
  • Light headedness
  • Shortness of breath
  • Rapid heart rate
  • Trouble concentrating
  • Allergic reactions
  • Sores or white patches in mouth or throat.

Meropenem may interact with certain medicines such as divalproex sodium, probenecid, or valproic acid. Other prescription and over-the-counter drugs such as vitamins and herbal medicines may also interact with meropenem.


Ceftazidime is used for the treatment of infections that are caused by bacteria. It belongs to the cephalosporin class of drugs. Ceftazidime is known to stop the growth of bacteria. The drug can be injected into the vein or muscles in every span of 8-12 hours. The dosage depends on the condition and the response to the treatment. Side effects include swelling and redness or pain at the injection site. Severe side effects include:

  • Muscle spasms
  • Stomach or abdominal pain
  • Changes in mood
  • Easy bruising or bleeding
  • Kidney or liver issues
  • Tiredness
  • Shaking
  • Loss of appetite

Ceftazidime may also decrease the effectiveness of other antibiotics such as rifampin or rifabutin.


Tobramycin inhalation is prescribed for people with cystic fibrosis caused by the Pseudomonas aeruginosa bacterium. This bacterium causes lung infection in people who have weak immune systems. Tobramycin is available under the brand names TOBI, Bethkis, or as inhalation dry powder under the brand name TOBI Podhaler. This antibiotic is a non-pyrogenic aqueous solution. The pH and salinity is adjusted so that it can be administered as a compressed air and reusable nebulizer. Aerosolized tobramycin is widely used by cystic fibrosis patients. It directly delivers the antibiotic to the endobronchial infection site. It decreases the toxicity by limiting the systemic absorption.

In clinical trials, its use has ranged from 80mg twice or thrice daily to 600mg thrice daily. At a dose of 80mg, no significant improvement was seen when compared to the 600mg dose, which significantly improved clinical and pulmonary functions. It also reduced the density of Pseudomonas aeruginosa in the sputum. Common side effects of tobramycin include:

  • Cough
  • Runny and stuffy nose
  • Discolored sputum
  • Fever
  • Difficulty breathing

Some of the less common side effects of tobramycin include:

  • Hearing loss
  • Trouble urinating
  • Sore throat
  • Swollen glands
  • Unusual bleeding
  • Bruising
  • Tiredness


Amikacin is used for the treatment of bacterial infections in patients suffering from cystic fibrosis. It also prevents many bacterial infections. Amikacin belongs to the amino glycoside antibiotics class of drugs and works by stopping the bacteria from growing. This medicine can be administered intravenously. The dosage of this medicine would depend on the condition of the patient. It is injected into a muscle or vein. Treatment is no longer than 14 days. The side effects of amikacin include:

  • Stomach pain
  • Loss of appetite
  • Irritability
  • Nausea
  • Vomiting
  • Irritation or redness at the site of injection.

Amikacin sulfate is derived from kanamycin. This medicine is a semi synthetic aminoglycoside antibiotic which is available as a sterile, colorless to straw-colored solution for the purpose of IV usage. 

Penicillin Antibiotics for Cystic Fibrosis

Piperacillin and Tazobactam

Piperacillin and tazobactam injection is used to treat infections of bacteria. It is used in many different body parts. This particular combination belongs to the penicillin and beta-lactamase inhibitors group of medicines. They work by killing the bacteria and preventing further bacterial growth. Before using this medicine, the benefits should be judged against its side effects. This decision is made by the doctor and the patient. This medicine is injected into the vein slowly. A common side effect is diarrhea. The less common side effects include:

  • Blurred vision
  • Nausea
  • Headache
  • Fever
  • Vomiting
  • Stomach pain
  • Sweating
  • Irregular heartbeat.
  • Inflammation of the injection site.

Rare side effects include:

  • Bone pain
  • Stomach cramps
  • Agitation
  • Allergic reactions
  • Lethargy

Tazocin is a brand name of this antibiotic. The usual dose for adults with CF is 4.5 grams every 6 hours by IV. It lasts for 10-14 days.

Regular Antibiotics vs Penicillin Antibiotics

Cystic fibrosis clogs the airways with mucus, causing infection which can also lead to breathing failure and potentially death. Thus, patients are sometimes given regular antibiotics to treat or prevent infection. A review was conducted wherein 401 children were put into groups at random and received either an oral antibiotic or no antibiotic treatment. It was found that there was not much difference between giving regular antibiotics or not.

The first line of treatment used to treat cystic fibrosis infection with P. aeruginosa is extended-spectrum penicillin, aminoglycosides, cephalosporins, fluoroquinolones, and monobactams. An aminoglycoside with beta-lactam penicillin is considered as first line treatment. Penicillin is also a potential choice of treatment for cystic fibrosis patients who develop bacterial infections. Penicillin attacks the bacterial cell wall made of peptidoglycan. They weaken the cell wall and by osmotic pressure cause the cells to rupture and die. It directly kills the bacteria and also prevents its growth.


Those with medication allergies, reduced liver or kidney functions, or women who are pregnant or breastfeeding should take antibiotics with extreme caution. Patients taking antibiotics should not take any other medications, or herbal medicines, without first consulting a doctor. Over-the-counter medicines or non-prescription medicines may also interact with antibiotics. Penicillin, cephalosporins, and some antibiotics may make oral contraceptive ineffective; thus, it is recommended that an additional contraceptive be used while taking antibiotics.