In medical science and health, new and innovative achievements in the field of developing drugs and medical treatments are continuously achieved. Gentamicin ointment is one of the drugs that is well known in the medical field and has a significant effect in the treatment of bacterial infections. The main ingredient of this ointment is gentamicin, which is used as an effective tool in dealing with skin infections and bacterial damage. In this article, we will review important details such as uses, side effects, contraindications and precautions, mechanism of action, etc. of gentamicin ointment.
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Pharmaceutical forms of gentamicin
Chemical and herbal medicines available in the market are produced in different pharmaceutical forms based on international standards and classes. These forms include tablets, capsules, serum, ointment, injectable solution, syrup, etc., which the doctor prescribes according to the medical records, physical condition and age of the patient. Gentamicin in the form of eye drops, ointment or cream 1%, injection solution 10 mg and 40 mg, intravenous solution 60 mg, 70 mg, 80 mg, 90 mg, 100 mg and 120 mg in Pharmacies are produced.
Uses of gentamicin
The eye drops of this product are used to treat bacterial infections (such as blepharitis, conjunctivitis) of the eye and the skin around the eye (such as the eyelid). It is also used to prevent infection after eye injury or surgery. This drug belongs to a class of drugs known as aminoglycoside antibiotics. Unnecessary use or incorrect use of any antibiotic can lead to a decrease in its effectiveness. The most important uses of this product are in sensitive infections, surgical prophylaxis (off-label), treatment of infectious endocarditis, Staphylococcus aureus, pelvic inflammatory disease (off-label), plague treatment, etc.
Uses of gentamicin in adults
- Sensitive infections
- Surgical prophylaxis
- Treatment of infective endocarditis
- Staphylococcus aureus
- Pelvic inflammatory disease
- Plague treatment
Uses of gentamicin in children
- Sensitive infections
- Surgical prophylaxis, before surgery
Pharmacological effects and mechanism of action of Gentamicin drug
The mechanism of action of gentamicin is an aminoglycoside antibiotic for covering Gram-negative bacteria, including Pseudomonas species. Also synergistic with beta-lactamase against enterococcus; It interferes with bacterial protein synthesis by binding to 30S and 50S ribosomal subunits. Distribution of gentamicin crosses the placenta and relative diffusion from blood to CSF is minimal even with inflammation. Excretion of this drug occurs through urine (70% recovered as unchanged drug in patients with NRF).
Dosage of gentamicin eye drops
To use eye drops, wash your hands first. To avoid contamination, do not touch the dropper tip or allow it to touch your eyes or any other surface. Avoid swallowing or injecting eye drops. Tilt your head back, look up and lower the lower eyelid. Hold the dropper directly over your eye and put one drop into the eye as directed by your doctor. Look down, close your eyes slowly and place one finger in the corner of your eye (nearsightedness). Apply gentle pressure for 1-2 minutes before opening your eyes.
How to use gentamicin in adults
- Susceptible infections: Use total body weight (TBW) instead of ideal weight to treat this disease in underweight and non-obese patients. The usual dose is 3-5 mg every 8 hours for general use.
- Surgical prophylaxis: the dose is 5 mg before surgery. If the patient weighs more than usual, the dose should be increased according to the doctor’s order.
- Cystic fibrosis: The dosage for the treatment of cystic fibrosis is 5-10.5 mg divided every 8 hours.
- Pelvic inflammatory disease: the recommended dose is 1.5 mg every 8 hours for 3 to 5 days. Transition from parenteral to oral therapy with oral doxycycline or oral clindamycin may also be initiated within 24 to 48 hours of clinical improvement for the full 14-day treatment period.
- Plague treatment: To treat plague with a doctor’s prescription, usually 5 mg per day for 10 days. The use and continuation of the drug depends on the fever and severity of the disease and should be determined by the doctor.
How to use gentamicin in children
- Sensitive infections: the dose used in children is determined based on the child’s weight. The general consumption amount in infants is 2.5 mg every 8 hours and in children and adolescents 2 to 2.52 mg every 8 hours.
- Surgical prophylaxis, before the operation: the dosage for children is determined based on the actual body weight. However, the recommended dose for children is 2.5 mg one hour before surgery.
- It should be used in children with medical records of peritoneal dialysis, kidney or liver disorders, digestive problems, etc. with a doctor’s prescription.
Time to use gentamicin ointment
Gentamicin topical ointment or cream is only for external use on the skin of the body, it is forbidden to use the ointment of this product on internal parts of the body (such as eyes, mouth or inside the ear). Of course, patients can use its ointment on parts of the lips, corners of the eyes or on the ears with a doctor’s prescription. Before using the ointment, read the drug information on its package carefully. The manufacturer of the drug has included detailed information about the time to use the ointment or eye drops for you. Note that the time of use stated on the medicine is for general use, see your doctor to get the best prescription.
Before using gentamicin, carefully read the drug information on the product packaging. If you are allergic or allergic to this medicine or other aminoglycoside antibiotics (such as tobramycin), avoid using the medicine. This product may contain inactive ingredients that can cause allergic reactions or other problems. After taking this medicine, you may experience blurred vision, if this problem occurs, avoid driving, working with heavy equipment, tools, etc. This drug may pass into breast milk, consult your doctor before breastfeeding.
- Patients treated with aminoglycosides should be closely monitored clinically. There is a high risk of toxicity associated with their use.
- Risk of ototoxicity has been reported in some patients, tinnitus or vertigo may be a sign of vestibular damage and irreversible bilateral damage. Discontinue treatment if signs of ototoxicity occur.
- Use with caution in cases of renal failure (not dialysis), myasthenia gravis, hypocalcemia and conditions that reduce neuromuscular transmission.
- Diuretics may increase aminoglycoside toxicity by altering serum and tissue antibiotic concentrations. Some diuretics themselves may cause ototoxicity. Avoid strong diuretics, including ethacrynic acid or furosemide.
- Use caution in patients with electrolyte disturbances including hypocalcemia, hypomagnesemia, or hypokalemia.
- Use caution in patients with neuromuscular disorders, including myasthenia gravis.
- It is dangerous to use this product in patients with hearing and kidney failure, these people should only take this medicine with a doctor’s prescription.
Contraindications to the use of gentamicin ointment
Contraindications and precautions of gentamicin are stated in the drug information of the product. The most important contraindications for this product include toxicity or hypersensitivity to previous aminoglycosides and hypersensitivity. However, before taking this medicine, you should pay attention to some important points that we will discuss further.
- Patients treated with aminoglycosides should be closely monitored due to the potential toxicity associated with their use.
- Neurotoxicity, manifested as bilateral auditory and vestibular ototoxicity, can occur in patients with pre-existing renal impairment and in patients with normal renal function who are treated with higher doses or longer durations than recommended.
- Aminoglycosides are potentially nephrotoxic. The risk is higher in patients with impaired renal function and in those receiving high doses or long-term treatment.
- Consider eighth cranial nerve and renal function monitoring, especially in patients with decreased or suspected renal function at initiation of therapy.
- The drug should be used with caution in premature babies and infants due to kidney failure and as a result prolongation of the serum half-life.
- Neuromuscular blockade and respiratory paralysis have been reported following injection of this drug solution, local induction (such as orthopedic and abdominal lavage or in the local treatment of empyema), and oral use of aminoglycosides, especially when administered immediately after anesthesia or muscle relaxants. .
- Avoid strong diuretics (eg, ethacrynic acid, furosemide) as they increase the risk of ototoxicity.
- Avoid simultaneous or consecutive use of neurotoxic or nephrotoxic drugs, including other aminoglycosides (eg, amikacin, streptomycin, neomycin, kanamycin, paromomycin).
Gentamicin side effects
Eye irritation, blurred vision, itchy eyes, etc. are some of the side effects reported in eye drops and itching, swelling, skin sensitivity, etc. are some of the side effects of gentamicin ointment. If any of these effects persist or worsen, tell your doctor or pharmacist right away. Most people who use this drug do not experience serious side effects. Using this medicine for long or frequent periods may lead to other types of eye infections, including fungal infections. If you notice new eye symptoms such as pain, swelling, thick discharge or severe pus in the patient, stop taking the medicine and see a doctor.
- Neurotoxicity (vertigo, ataxia)
- Instability of walking
- ototoxicity (auditory, vestibular)
- Nephrotoxicity (CrCl depletion)
- Nephrotoxicity if less than 2 mg/L
- Nausea, vomiting, weight loss and anorexia
- Redness of the skin
Drug interaction of gentamicin
Drug interactions may change how your medications work or increase your risk of serious side effects. Patients, prepare a list of chemical and herbal medicines you use and show it to the doctor. The doctor prescribes the best medicine for you according to the drugs you are taking so that side effects and drug interactions do not occur. Drugs such as agalsidase alfa, agalsidase beta, ataluren, cholera vaccine, foscarnet, mannitol (systemic), mecamylamine, methoxyflurane, etc. cause drug interactions with gentamicin.
Use of gentamicin during pregnancy and breastfeeding
Gentamicin enters breast milk, so avoid self-administration without a prescription. There is no specific information and research regarding the risks of using this product on pregnant women and fetuses. Animal studies have not shown any risk and many human studies are not available. If the benefits are greater than the risks, it can be consumed with a doctor’s prescription.
Storage conditions for gentamicin
Ointment, injection solution and gentamicin drops should be stored at room temperature (preferably cool) away from light and moisture. Keep all chemical and herbal medicines out of the reach of children and animals. Dispose of this product properly when it has expired or is no longer needed. Avoid pouring all kinds of medicines into wells, streets and sewers.
The last word of gentamicin ointment
In this article from Positive Green Online Pharmacy magazine, various forms of gentamicin and the introduction of this effective drug in dealing with skin and tissue infections were discussed. Finally, this ointment is very important as one of the basic tools in the treatment of skin and tissue infections. With complete information and judicious use of this drug, we can help improve the health of the skin and body tissues and manage bacterial infections as a major medical challenge. However, the use of gentamicin ointment requires caution and should be used according to the doctor’s instructions.
Site source: Medscape