What are the precautions for the use of antibacterial drugs?
Currently, for the treatment of bacterial diseases, the use of antibacterial drugs is still the main treatment method. If used irrationally, it will result in poor treatment efficacy and the development of drug resistance. Therefore, the following points should be noted when using antibacterial drugs:
1. Select the drug variety according to the pathogen. Do not use drugs blindly based on your own experience; large-scale pig farms should best conduct a drug sensitivity test first before choosing drugs.
2. The dosage administered should be reasonable. Within a certain dosage range, the larger the dose, the more obvious the efficacy, but the dose should not be blindly increased. For the treatment of acute infectious diseases, severe infections, and infections at sites difficult for antibacterial drugs to reach, the dosage of antibacterial drugs should be relatively large, and the first use should be doubled, after which the amount should be reduced as appropriate according to the condition or given at the conventional therapeutic dose. When antibacterial drugs are used in combination, with the help of synergistic antibacterial effects, the dosage of each variety can be appropriately reduced.
3. The dosage must be accurate. The amount of a drug used differs between the legal dosage and the clinical experience dosage. For drugs with toxic side effects, a narrow safety margin, and strict dosage requirements, such as mequindox, olaquindox, colistin, streptomycin, doxycycline, and sulfonamides, they should be used strictly according to the legal dosage, and the dosage must not be increased at will; at the same time, the dosage must be strictly calculated according to body weight.
4. Choose the number of administrations according to different drugs. Penicillins, cephalosporins, macrolides, and lincomycin are time-dependent drugs, and the time during which the drug concentration exceeds the minimum inhibitory concentration is the most critical factor for maintaining drug efficacy. When the concentration reaches a relatively high level, further increasing the concentration cannot increase its bactericidal effect; instead, efficacy should be improved by increasing the number of administrations. In contrast, aminoglycosides and fluoroquinolone antibacterial drugs have concentration-dependent characteristics. Under the condition that the daily dose remains unchanged, a single administration can achieve a greater blood drug concentration than multiple administrations per day, thereby significantly improving antibacterial activity and clinical efficacy, and reducing toxic side effects and injection stress, so a method of injecting once per day may be adopted, but the dose must be calculated according to the daily dose.
5. Administer according to the treatment course. The treatment course for disease varies with different infections. Generally, antibacterial drugs should be used continuously until body temperature is normal and for 48-72 hours after symptoms subside, completely killing the pathogens, so as to ensure stable efficacy. Never administer only 2-3 times, and once body temperature drops and symptoms ease, stop the drug too early, or immediately change the drug if no effect is seen; this can very easily lead to disease relapse or induce bacteria to develop drug resistance.
6. Master the principles for changing drugs. Because the therapeutic response to anti-infection treatment has a certain process, generally it is not advisable to change drugs during the first 72 hours, unless the condition clearly worsens or a change is needed based on the pathogen diagnosis results; if after 72 hours the efficacy is still not obvious, the drug should be changed promptly, and the medication should be adjusted according to the drug sensitivity test results. In addition, it should be noted that when changing drugs, it is not advisable to substitute one drug for another within the same class; drugs of different types should be selected as far as possible.
7. Choose the most appropriate route of administration. Intravenous injection can almost take effect immediately, followed in order by intramuscular injection, subcutaneous injection, and oral administration. For critical cases, intravenous injection or intravenous drip is preferable; for treating intestinal infections, oral administration is preferable; for severe digestive tract infections complicated by septicemia or bacteremia, oral administration should be combined with injectable administration. It should be pointed out that penicillin G is ineffective when taken orally and must be injected; aminoglycosides are difficult to absorb when taken orally, and for systemic treatment they must be administered by injection, while for treating intestinal infections they may be administered orally.
8. Follow the principles for combined use of antibacterial drugs. If one antibacterial drug can achieve the therapeutic purpose, combined use should not be readily adopted. However, in severe mixed infections or critical cases with unknown pathogens and dangerous conditions, combined medication may be used appropriately, but generally a combination of two drugs is sufficient.
Lyu Huixu