What Is Ethambutol?
Ethambutol is a chemically synthesized white, water-soluble, heat-resistant crystal. It can affect the synthesis of mycobacterium tuberculosis ribonucleic acid and has a killing effect. Doctors use ethambutol mainly for patients who have responded or contraindicated to streptomycin and sodium salicylate.
- Chinese name
- Ethambutol
- Foreign name
- ethambutol
- Molecular formula
- C10H24N2O2
- Molecular weight
- 204.3098
- Ethambutol is a chemically synthesized white, water-soluble, heat-resistant crystal. It can affect the synthesis of mycobacterium tuberculosis ribonucleic acid and has a killing effect. Doctors use ethambutol mainly for patients who have responded or contraindicated to streptomycin and sodium salicylate.
Brief introduction of ethambutol compounds
Ethambutol Basic Information
- Chinese name: ethylamino butanol
- Chinese alias: [2R, 2 [S- (R *, R *)]-R]-(+) 2,2 '-(1,2-ethylenediyldiimino) -bis-1-butanol;
- English name: ethambutol
- English alias: (+)-2,2-ethylenediiminodibutan-1-ol; 2,2 '-(ethane-1,2-diyldiimino) dibutan-1-ol; (2R, 2'R) -2,
- CAS number: 74-55-5
- Ethambutol molecular formula
- EINECS number: 200-810-6
- Molecular formula: C 10 H 24 N 2 O 2
- Molecular weight: 204.3098
- InChI: InChI = 1 / C10H24N2O2 / c1-3-9 (7-13) 11-5-6-12-10 (4-2) 8-14 / h9-14H, 3-8H2,1-2H3 / t9- , 10- / m1 / s1
- PSA: 64.52000
- LogP: 0.48920
Ethanol butanol physical and chemical information
- Density: 0.987g / cm 2
- Boiling point: 345.3 ° C at 760 mmHg
- Flash point: 113.7 ° C
- Vapor pressure: 3.9E-06mmHg at 25 ° C
- Appearance and properties: white crystal hygroscopic powder
- Melting point: 199-204ºC
- Refractive index: 1.5738 (20ºC)
- Storage conditions: Keep tightly closed. Store at 2-8ºC
Ethambutol safety information
- Customs code: 2922191000 [1]
Ethambutol drug description
Ethambutol pharmacological action
- This product is a synthetic bacteriostatic anti-tuberculosis drug. Its mechanism of action has not been fully elucidated. This product can penetrate into the body of the bacterial bacteria and interfere with the synthesis of RNA to inhibit the reproduction of bacteria. This product is only effective for the bacterial bacteria in the growth and reproduction period.
Ethambutol pharmacokinetics
- After oral administration, the absorption from the gastrointestinal tract is 75 to 80%. Widely distributed in all tissues and fluids (except cerebrospinal fluid) of the body. The concentration of the drug in the red blood cells is equal to or twice that of the plasma concentration, and can last for 24 hours. The drug concentration in the kidney, lung, saliva, and urine is high; but the concentration in the pleural fluid and ascites fluid is very low. This product cannot penetrate into the normal meninges, but there may be traces in the cerebrospinal fluid of patients with tuberculous meningitis. Its distribution volume is 1.6L / kg. The protein binding rate is about 10-30%. The peak plasma concentration can be reached within 2 to 4 hours after oral administration, and T1 / 2 is 3 to 4 hours. The renal function can be extended to 8 hours. Mainly metabolized by the liver, about 15% of the administered amount is metabolized into inactive metabolites. Through glomerular filtration and tubular secretion and excretion: about 80% are excreted within 24 hours after administration, at least 50% are excreted in the original form, and about 15% are inactive metabolites. About 20% are excreted in the feces in their original form. The concentration of the drug in milk is approximately equivalent to that of the mother's blood. A significant amount of ethambutol can be cleared from the body by hemodialysis and peritoneal dialysis.
Indications of ethambutol function
- It has a strong inhibitory effect on Mycobacterium tuberculosis and other mycobacteria. Oral absorption is about 80%, the peak time of blood concentration is 2 to 4 hours, protein binding is about 40%, and only about 10% of the drug is metabolized into inactive substances in the body. Mainly excreted by the kidneys. No cross-resistance with other anti-TB drugs. However, Mycobacterium tuberculosis can also slowly develop resistance to this product. It is a second-line anti-tuberculosis drug and can be used in cases in which other anti-tuberculosis drugs have failed to treat. It is often used in combination with other anti-tuberculosis drugs. To enhance the efficacy and delay the development of bacterial resistance. Ineffective dosage for intracellular tuberculosis
- 1. Commonly used doses for adults are combined with other anti-tuberculosis drugs. Tuberculosis is initially treated with 15 mg / kg of body weight once daily; TB is retreated with 25 mg / kg of body weight once daily for 60 consecutive days, followed by 15 mg / kg, once daily. Atypical Mycobacterium infection, 15-25mg / kg daily, once a day, and combined with other anti-TB drugs. 2. It is not suitable for children under 13 years of age to use this product; children over 13 years of age are the same as adults. If gastrointestinal irritation occurs, ethambutol can be taken with food. The effective blood concentration may not be reached in divided doses of a day, so this product should be taken once. Ethambutol can rapidly develop drug resistance when used alone, so this product must be used in combination with other anti-TB drugs. When this product is used in patients who have received antituberculosis drugs, it should be used in combination with at least one second-line drug, such as ethionamide or cycloserine. Treatment must last 1-2 years, sometimes even years or indefinitely. In addition, the intermittent therapy of ethambutol and isoniazid has achieved satisfactory results. The dose is 50mg / kg of ethambutol and 15mg / kg of isoniazid, and it is administered twice a week. In patients with impaired liver or kidney function, the blood concentration of this product may increase, and the half-life is prolonged. Patients with impaired renal function need to reduce the amount of this product.
Ethambutol adverse reactions
- (1) Those with a higher incidence are blurred vision, eye pain, red-green blindness, or any loss of vision (optic neuritis: easy to occur when the daily dose is above 25mg / kg). (2) Less frequent cases were chills, joint swelling and pain (especially big toe, palate, knee joint), and skin fever and tightness on the joint surface (acute gout, hyperuricemia). (3) The numbness is extremely rare, acupuncture, burning pain, or weakness in hands and feet (peripheral neuritis). Can cause gastrointestinal reactions: nausea, vomiting, loss of appetite, bloating, diarrhea. Individual cases include depression, headache, rash, hair loss, joint pain, acne, elevated transaminase, liver damage, lower limb numbness, joint pain and hallucinations, Anxiety, insomnia and other mental symptoms. Excessive dose, orthostatic hypotension, hyperuricemia, exfoliative dermatitis, blurred vision, convulsions, and even blindness.
Ethambutol contraindications
- (1) Ethambutol can penetrate the placenta, and the fetal plasma concentration is about 30% of the maternal plasma concentration. High doses of this product in mouse experiments can cause cleft lip, brain exposure, and spinal deformities; high doses of this product in rats can cause mild cervical spine deformities; high doses of this product in rabbits can cause unilateral deformities, short limbs, Deformities of rabbit lips and cleft palate. Although no problem has been proven in humans, pregnant women must still weigh the pros and cons fully. The effect of this product in combination with other drugs on the fetus has not been elucidated. (2) Ethambutol can be secreted into breast milk at a concentration similar to that of blood drug. Although no problem has been proven in humans, the benefits of lactating women should be weighed against the risks. (3) The following conditions should be used with caution: gout, optic neuritis, and impaired renal function. (4) There is no clinical data for children under 13 years of age. The elderly often have physiological renal dysfunction, so the dosage should be adjusted according to renal function. This product is contraindicated in patients with alcoholism and infants. Diabetics must use this product on the basis of controlling diabetes. This product should be used with caution in patients with diabetic fundus lesions to prevent the fundus lesions from becoming worse.
Ethambutol precautions
- 1. Visual neuritis. It mainly occurs in patients with large doses, and there may be blurred vision, blind spots in the center of vision, and reduced vision (scope of vision).
- 2, gastrointestinal discomfort, loss of appetite, abnormal liver function, and some may have allergic dermatitis and muscle soreness and joint pain.
- 3. Sometimes it will affect the kidney function. It should be used with caution for pregnant women, infants and patients with epilepsy. It is best to check it before use. When using it, you should closely observe the occurrence of side effects. For serious side effects, you should be under the guidance of a physician Stop the medicine in time.
Ethambutol drug interactions
- (1) Combination with ethionamide can increase side effects. (2) Use with aluminum hydroxide can reduce the absorption of ethambutol. (3) Combination with neurotoxic drugs can increase the neurotoxicity of this product, such as optic neuritis or peripheral neuritis.
Ethambutol hydrochloride capsule preparation
- English name EthambutolHydrochlorideCapsules
- Category: Western medicine
- Pharmacological action
- 1. Pharmacology This product is a synthetic antibacterial tuberculosis drug. It has strong activity against bacteria during growth and reproduction, and has little effect on bacteria at rest. High antibacterial activity against all types of mycobacteria. There is no cross-resistance between Mycobacterium tuberculosis and this drug. The mechanism of action of this product has not been fully elucidated. It may be related to inhibiting the metabolism of sensitive bacteria, inhibiting the synthesis of RNA, and interfering with the protein metabolism of Mycobacterium tuberculosis, leading to bacterial death. 2. Toxicology This product can cause cleft palate, brain exposure, and spinal deformity in mouse tests at large doses; it can cause mild cervical spine deformity in rat tests; and it can cause one-eye, short limbs, and cleft palate in rabbit tests. This product is a capsule.
- dynamics
- After oral administration, this product absorbs 75% to 80% through the gastrointestinal tract, and the peak time is 2 to 4 hours. It is widely distributed in various tissues in the body and can be concentrated in red blood cells (the concentration of red blood cells can reach 2 to 3 times the blood drug concentration), kidney, lung, saliva, and urine, and the concentrations in pleural fluid and ascites are extremely low. The concentration of the drug in the cerebrospinal fluid is about 20% to 80% of the blood concentration, the apparent volume of distribution (Vd) is 1.6 to 3.9L / kg, and the protein binding rate is about 10% to 30%. The blood elimination half-life (T1 / 2a) is 2.5 to 4 hours, and those with impaired renal function can be extended to 7 to 15 hours. Therefore, dose adjustment should be performed. About 10% to 20% of this product is metabolized in the liver. This product is excreted through glomerular filtration and tubular secretion. About 50% to 90% of the drug is excreted through the kidney within 24 hours after administration. About 15% is Inactive metabolites, renal clearance (ClR) is 5.93 to 8.45 ml / min / kg. About 20% are excreted in the feces in their original form. The drug concentration in breast milk is approximately equivalent to the maternal blood drug concentration. Hemodialysis and peritoneal dialysis can clear this product.
- Indication
- This product is suitable for the treatment of tuberculosis and extrapulmonary tuberculosis caused by Mycobacterium tuberculosis in combination with other anti-tuberculosis drugs. It can also be used for the treatment of atypical Mycobacterium tuberculosis infection.
- Dosage
- Need to be combined with other anti-TB drugs. 1. Initial treatment: Orally, according to body weight 15mg / kg, once a day; or 25-30mg / kg once, up to 2.5g, three times a week; or 50mg / kg, up to 2.5g twice a week. 2. Retreatment: Orally, 25mg / kg once a day for 60 consecutive days, followed by 15mg / kg once a day. 3 Atypical Mycobacterium tuberculosis infection: 15 to 25 mg / kg, once a day.
- Adverse reactions
- 1. Common optic nerve damage, such as retrobulbar optic neuritis, optic nerve center fiber damage. It may be related to the reduction of the content of these metal elements after chelation of this product with copper, zinc and other metal elements. The incidence of retrobulbar optic neuritis is about 0.8%, which is related to the dosage and course of treatment. It is easy to occur when long-term medication and daily dose is greater than 25mg / kg. The incidence rate of daily dose of 15mg / kg is 1%, 25mg / kg is 6%, and 35mg. / kg increased to 15%. Presented as blurred vision, eye pain, red-green blindness or vision loss, reduced vision. The early detection of these reactions and the timely discontinuation of the drug can disappear on their own within weeks or months, and permanent loss of visual function rarely occurs. 2. Rarely, chills, joint swelling and pain (especially big toe, palate, knee joint), and fever and tightness of the skin of the affected joint surface (acute gout, hyperuricemia). 3 Occasionally gastrointestinal discomfort, nausea, vomiting, diarrhea, liver damage, peripheral neuritis (often manifested as numbness, acupuncture, burning pain or weakness of hands and feet) and allergic reactions (often manifested as rash, itching, headache, Fever, joint pain), etc.
- Taboo
- People with allergies to this product, patients with known optic neuritis, alcoholism, and those younger than 13 years of age should be used with caution.
- Precautions
- 1. Gout, optic neuritis, diabetic fundus disease, liver and kidney function should be used with caution. Patients with reduced renal function should be reduced. 2. This product alone can quickly develop drug resistance, so it must be used in combination with other anti-TB drugs. 3 During the treatment, check: (1) the eye, visual field, vision, red and green discrimination, etc., check once a month before the medication and during the course of treatment, especially for patients with a long course of treatment and a daily dose of more than 15 mg / kg. (2) Because this product can increase the concentration of uric acid in the blood and cause gout attacks, the serum uric acid should be measured regularly during the course of treatment. 4 Interference to diagnosis: Taking this product can increase the measured value of blood uric acid concentration. 5. If gastrointestinal irritation occurs, this product can be taken with food. The daily dose may not reach the effective blood concentration, so the daily dose of this product should be taken once. There is no clinical data for children under 13 years of age. Because it is not easy to monitor vision changes in young children, this product is not suitable for children under 13 years of age; children over 13 years of age are the same as adults. 1. Because this product can penetrate the placenta, the fetal blood concentration is about 30% of the maternal blood concentration. Animal experiments have shown that this product can cause deformities. Although no problem has been confirmed in humans, pregnant women should still disable this product Pros and cons should be fully weighed when taking indications. 2. This product can be secreted into milk, and its concentration is similar to the blood concentration of the mother. Therefore, this product is forbidden for lactating women. If there are indications, lactation should be suspended. Elderly patients should adjust the dosage according to renal function due to physiological renal failure.
- Excessive treatment 1. Drug overdose is mainly manifested in the symptoms described in the severe case, permanent optic atrophy can occur in severe cases. 2. Treatment of drug overdose: (1) discontinuation of drug. (2) Symptomatic treatment: Those with posterior optic neuritis can use vitamin B6, multivitamins, and zinc-copper preparations. To restore vision, 5mg of dexamethasone can be used as a daily intravenous infusion or post-ball injection; 12.5mg of torasulin can be administered as a post-ball injection; hydrocortisone 200mg can be administered daily as an intravenous drip. Prednisone 20mg can also be taken orally 2 to 3 times a day. Vitamins are given at the same time. During the recovery period, acupuncture treatment can be given, oral dibazole, niacin, etc., or daily intramuscular injection of placental tissue fluid. Perform hemodialysis and peritoneal dialysis if necessary.
- interaction
- 1. Aluminum salts, including DDI buffers, can reduce the absorption of this product. 2. The combination of this product with verapamil can reduce the absorption of the latter. 3 Combination with neurotoxic drugs can increase the neurotoxicity of this product, such as optic neuritis or peripheral neuritis. 4 Combination with ethionamide can increase adverse reactions such as jaundice hepatitis and optic neuritis.
Ethambutol hydrochloride tablets
- Category: Western medicine
- Pharmacological action
- This product is a synthetic bacteriostatic anti-tuberculosis drug. Its mechanism of action has not been fully elucidated. This product can penetrate into the body of mycobacteria to interfere with the synthesis of RNA, thereby inhibiting the reproduction of bacteria. This product is only effective for mycobacteria during growth and reproduction. To date, no cross-resistance has been found between this product and other anti-TB drugs. This product is a white tablet.
- dynamics
- After oral administration, 75% to 80% are absorbed through the gastrointestinal tract. Widely distributed in body tissues and fluids (except cerebrospinal fluid). The drug concentration in red blood cells is equal to or equal to the plasma concentration and can last for 24 hours; the drug concentration in kidney, lung, saliva, and urine is higher; but the concentration in pleural fluid and ascites is lower. The protein binding rate is about 20% to 30%. The peak plasma concentration can be reached in 2 to 4 hours after oral administration, and the half-life (T1 / 2) is 3 to 4 hours. Those with impaired renal function can be extended to 8 hours. Mainly metabolized by the liver, about 15% of the administered amount is metabolized into inactive metabolites. It is excreted by glomerular filtration and tubular secretion; about 80% is excreted within 24 hours after administration, at least 50% is excreted in its original form, and about 15% are inactive metabolites. About 20% are excreted in the feces in their original form. The concentration of the drug in milk is approximately equivalent to the concentration of the drug in the mother's blood. A significant amount of ethambutol can be cleared from the body by hemodialysis and peritoneal dialysis.
- Indication
- It is suitable for treating tuberculosis caused by Mycobacterium tuberculosis in combination with other anti-TB drugs. Can also be used for the treatment of tuberculous meningitis and atypical mycobacterial infections.
- Dosage
- 1. Commonly used amount for adults combined with other antituberculosis drugs, tuberculosis treatment, 15mg / kg body weight, once daily; or 25-30mg / kg orally each time, up to 2.5g, 3 times a week; or 50mg / kg, up to 2.5g, twice a week. Re-treatment of tuberculosis should be given once daily at a dose of 25 mg / kg for 60 consecutive days, followed by once daily at a dose of 15 mg / kg. Atypical mycobacterial infection, 15-25mg / kg daily, once a day; 2. Commonly used in children is not suitable for the use of this product under the age of 13; Children over 13 years of age are the same as adults.
- Adverse reactions
- 1. The incidence is more blurred vision, eye pain, red and green blindness or vision loss, visual field reduction (opinous neuritis is easy to occur when the daily dose is more than 25mg / kg). Visual changes can be unilateral or bilateral; 2. Less frequent cases are chills, joint swelling and pain (especially big toes, plantar and knee joints), and fever and tightness of the skin on the affected joint surface (acute gout, hyperuricemia) Allergic reactions such as rash, fever, joint pain, or numbness, acupuncture, burning pain, or weakness in hands and feet (peripheral neuritis).
- Precautions
- 1. Interference to diagnosis: taking this product can increase the measured value of blood uric acid concentration; 2. It should be used with caution in the following cases: gout, optic neuritis, renal dysfunction; 3. check during treatment: eye, visual field, vision, Red and green discrimination, etc., check once a day before and during the course of treatment, especially for patients with a long course of treatment and a daily dose of more than 15 mg / kg; serum uric acid measurement, because this product can increase the serum uric acid concentration, causing gout attacks. Therefore, it should be measured regularly during the course of treatment; 4. If gastrointestinal irritation occurs, ethambutol can be taken with food. The daily dose may not reach the effective blood drug concentration, so this product should be taken once daily. 5. Ethambutol can quickly develop drug resistance when used alone, so it must be combined with other anti-TB drugs. application. When this product is used in patients who have received antituberculosis drugs, it should be combined with at least one drug; 6. Given that there is no practical method for measuring blood concentration in 2013, the dose should be calculated based on the patient's weight. In patients with impaired liver or kidney function, the blood concentration of this product may increase, and the half-life is prolonged. Patients with impaired renal function need to reduce the dose. No clinical data are available for children under 13 years of age. Because it is not easy to monitor vision changes in young children, this product is not recommended for children under 13 years of age. 1. Ethambutol can penetrate the placenta, and the fetal plasma concentration is about 30% of the maternal plasma concentration. High doses of this product in mouse experiments can cause cleft palate, brain exposure, and spinal deformities; 2. Ethambutol can be distributed to breast milk at a concentration close to that of blood, although it has not been proven to be a problem in humans, and is used in lactating women We must weigh the pros and cons. Elderly people are often accompanied by physiological renal dysfunction, so the dosage should be adjusted according to renal function.
- medicine interactions
- 1. Combination with ethionamide can increase adverse reactions; 2. Use with aluminum hydroxide can reduce the absorption of this product; 3. Use with neurotoxic drugs can increase the neurotoxicity of this product, such as optic neuritis or peripheral neuritis .
Ethambutol toxicity
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2. Hematological toxicity-increased eosinophils 3. Nutrition and metabolic system toxicity-elevated body temperature |
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3. Kidney, ureter and bladder toxicity-changes in urine components |
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2. Immune system toxicity-anaphylactic shock |
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- [3] [3] [4-9]