Amikacin Injection

Amikacin sulfate injection is a short-term antibiotic treatment for serious bacterial infections caused by susceptible bacteria. It is used across a wide range of infection types:

• Bacterial septicemia (blood infection), including neonatal (newborn) sepsis
• Serious respiratory tract infections
• Bone and joint infections
• Central nervous system infections, including meningitis (infection of the membranes around the brain and spinal cord)
• Skin and soft tissue infections
• Intra-abdominal infections, including peritonitis (infection of the abdominal lining)
• Burn infections and serious postoperative infections, including post-vascular surgery
• Serious complicated or recurrent urinary tract infections caused by susceptible gram-negative bacteria
• Infections caused by bacteria resistant to gentamicin or tobramycin, such as Pseudomonas aeruginosa and Serratia marcescens
• Certain staphylococcal infections, especially in patients allergic to other antibiotics or when both gram-positive and gram-negative bacteria may be involved

Amikacin is an aminoglycoside antibiotic. It works by binding tightly to the prokaryotic ribosome — the machinery inside bacterial cells that builds proteins. Without the ability to make proteins, bacteria cannot survive or multiply, so amikacin kills them directly. It is effective against a broad range of gram-negative bacteria and some gram-positive bacteria, particularly staphylococci.

One key advantage of amikacin is that it resists breakdown by many of the enzymes bacteria use to inactivate other aminoglycosides like gentamicin and tobramycin. This makes it useful when infections don't respond to those drugs. Amikacin also works synergistically with beta-lactam antibiotics (like penicillins) against many gram-negative organisms, meaning the two drugs together are more effective than either alone.

Amikacin sulfate injection is given only by injection — either into a muscle (intramuscular) or slowly into a vein (intravenous). Dosing is carefully calculated based on your body weight and kidney function, and is typically given two to three times per day. Intravenous doses are infused over 30 to 60 minutes for adults; infants receive their dose over 1 to 2 hours.

• Treatment usually lasts 7 to 10 days; safety beyond 14 days has not been established
• Patients with kidney problems need a reduced dose or longer time between doses — your care team will adjust this
• Amikacin must never be mixed in the same IV line with other medications
• Always follow your prescriber's exact instructions, and attend all scheduled blood and kidney tests

Like all aminoglycosides, amikacin carries a risk of serious side effects — primarily involving hearing and kidney function. Other reported side effects include:

• High-frequency hearing loss (may occur before you notice it)
• Ringing, roaring in the ears, or dizziness/vertigo
• Kidney changes: reduced urine output, elevated creatinine, protein in urine
• Numbness, tingling, or tremor
• Nausea and vomiting
• Skin rash or drug fever
• Low magnesium levels in the blood (hypomagnesemia)
• Anemia or low blood pressure (reported rarely)

Hearing loss from amikacin can be permanent and may worsen even after the drug is stopped — report any changes in hearing, ringing, or balance to your care team immediately. Kidney changes are usually reversible when the drug is stopped, but serious kidney failure has been reported.

• Permanent hearing loss: Amikacin can permanently damage the nerves responsible for hearing and balance. High-frequency hearing loss often starts silently. Warning signs include ringing in the ears, dizziness, or muffled hearing — report these immediately.
• Kidney damage: Amikacin can harm the kidneys, especially in people with pre-existing kidney problems, the elderly, or those who are dehydrated. Kidney function must be monitored throughout treatment.
• Neuromuscular blockade: Amikacin can cause sudden muscle paralysis and breathing failure, particularly in patients receiving anesthetics or muscle-relaxing drugs. Emergency respiratory support may be needed.
• Genetic risk for hearing loss: People with certain mitochondrial DNA variants (especially MT-RNR1 m.1555A>G) can develop permanent hearing loss even at normal amikacin blood levels. Tell your doctor if there is a family history of aminoglycoside-related hearing loss.
• Pregnancy: Aminoglycosides can cause permanent deafness in an unborn baby. Amikacin should only be used during pregnancy if absolutely necessary.
• C. difficile colitis: Like all antibiotics, amikacin can trigger a serious gut infection (C. difficile) causing severe diarrhea that may require separate treatment.
• Sulfite allergy: This injection contains sodium metabisulfite, which can cause serious allergic reactions in sulfite-sensitive patients, particularly those with asthma.

Amikacin interacts with several drugs that can increase toxicity risk or affect how the body handles the antibiotic:

• Other aminoglycosides (e.g., gentamicin, tobramycin, kanamycin) — combined use greatly raises the risk of hearing and kidney damage
• Nephrotoxic drugs (e.g., amphotericin B, vancomycin, cisplatin, colistin, polymyxin B, cephaloridine, paromomycin, bacitracin, viomycin) — increase risk of serious kidney damage
• Potent diuretics (furosemide, ethacrynic acid) — can cause hearing damage on their own and amplify amikacin toxicity by altering drug levels in the blood and tissues
• Neuromuscular blocking agents (e.g., succinylcholine, tubocurarine, decamethonium) — combined use can cause dangerous muscle paralysis and breathing failure
• Anesthetics — may worsen the risk of neuromuscular blockade when given alongside amikacin
• Citrate-anticoagulated blood transfusions — large transfusions may increase neuromuscular blockade risk

This is not a complete list of interactions. Always talk with your doctor or pharmacist before starting, stopping, or changing any medication.

• Tell your doctor if you have any history of kidney disease or reduced kidney function — amikacin dosing must be adjusted and kidneys must be monitored closely
• Tell your doctor if you or a family member has experienced hearing loss related to aminoglycoside use, or if you have a known mitochondrial DNA variant (MT-RNR1) — you may be at much higher risk for permanent hearing loss
• Tell your doctor if you are pregnant or planning to become pregnant — aminoglycosides can cause irreversible deafness in an unborn baby
• Tell your doctor about all other medications you take, especially other antibiotics, diuretics, or anesthetics
• Tell your doctor if you have asthma or a known sulfite sensitivity — this injection contains sodium metabisulfite
• Tell your doctor if you are allergic to amikacin or any other aminoglycoside antibiotic (cross-sensitivity is possible)
• Older adults are at higher risk for hearing and kidney toxicity and need careful monitoring
• Patients who are dehydrated are at increased risk of toxicity — stay well hydrated unless told otherwise by your care team
• Newborns require special dosing calculated by weight and age — inform the care team of all relevant details

Too much amikacin can cause serious hearing damage, kidney failure, and muscle paralysis. If an overdose is suspected, medical staff can remove amikacin from the body using peritoneal dialysis or hemodialysis (blood filtering procedures). In newborns, an exchange transfusion may also be considered. Seek emergency medical care immediately.

After an intramuscular injection, amikacin is absorbed rapidly, with peak blood levels typically reached within 1 hour. After intravenous infusion over 30 minutes, peak blood levels occur at the end of the infusion. The drug's serum half-life is slightly over 2 hours in people with normal kidney function, meaning the body clears roughly half the drug every 2 hours.

Amikacin is eliminated almost entirely unchanged through the kidneys (by glomerular filtration), with about 91–98% of an intramuscular dose excreted in the urine within 24 hours. It distributes well into many body tissues including bone, lung, heart, and gallbladder, and penetrates into spinal fluid when the meninges are inflamed. In people with impaired kidney function, the drug is cleared much more slowly, significantly prolonging its half-life and increasing the risk of toxicity — which is why dose adjustments are essential in those patients. Amikacin crosses the placenta and reaches the fetus.

Store at 20° to 25°C (68° to 77°F).