Toothache eat metronidazole generally 30 minutes to an hour or so to start to see the effect, for some chronic inflammation may need to take about 2 days to basically eliminate the pain, for neuropathic pain caused by toothache, eat metronidazole may not be effective. 1. Conventional inflammation: general gingivitis, periodontitis and other diseases caused by toothache, you can take metronidazole to anti-infection treatment, the drug into the body metabolic cycle after the general half an hour to an hour or so to start to see the effect of the pain slowly reduce. 2. Chronic inflammation: for teeth with chronic periapical inflammation caused by toothache symptoms, generally take metronidazole after a short period of time and can not immediately see the effect, need to use in accordance with the doctor’s instructions for about 1 to 2 days to basically eliminate the inflammation, to achieve the role of pain relief. 3. Neuropathic pain: metronidazole belongs to the antibiotic class of drugs, can inhibit the reproduction of anaerobic bacteria to achieve the role of anti-inflammatory pain relief, but for dental nerve inflammation caused by dental pulpitis, dentin allergy, and trigeminal neuralgia, etc., can not stop the pain, the need for oral ibuprofen to analgesia. Metronidazole needs to be used under the professional guidance of a doctor, and alcohol is prohibited during the medication to prevent the occurrence of disulfiram reaction, jeopardizing the safety of life, toothache in addition to the use of medication, it is more important to need to be directed at the dental pathogenesis of the corresponding treatment.