Isoniazid is an antibiotic that is prescribed to treat tuberculosis. Its mechanism is not very well known, but it’s believed that prevents the tuberculosis bacteria from making mycolic acids.
There are two stages in the treatment for tuberculosis. The first one lasts two months and the treatment is aimed to kill as many bacteria as possible. Isoniazid is used with other medicines at the same time such as pyrazinamide, rifampicin and ethambutol. After this type of treatment, the second stage lasts four months and some medicines are stopped, but isoniazid is still used.
Isoniazid is efficient in treating tuberculosis, but there are cases when it should be used with caution:
- slow liver metabolism
- decreased kidney function
- elderly people
- decreased liver function
- HIV infection
- psychotic illness
- hereditary blood disorders such as porphyrias
Related to pregnancy and breastfeeding, the safety of isoniazid hasn’t been established. If you are pregnant or you plan a pregnancy, inform your doctor before using any medicine.
When you take isoniazid, you have to pay attention to a few things:
- have a blood test to see if your liver function is alright before taking this medicine
- take each dose of this antibiotic regularly as the doctor prescribed it
- each dose should be taken at least 30 minutes before a meal or two hours after a meal
Any medicine may have side effects and isoniazid is not an exception. It may cause:
- dry mouth
- difficulty urinating
- loss of contact with reality
- blood disorders
- skin reactions
- inflammation of the liver
- inflammation of the nerves
- raised blood sugar levels
Additionally, isoniazid may increase the side effects of other medicines:
- Benzodiazepines, eg diazepam, triazolam
There are also other medicines that contain isoniazid: rifinah – contains isonizid and rifampicin, as well as rifater – a combination of isoniazid, rifampicin and pyrazinamide.
Isoniazid has to be kept in its container and out of reach of children. It has to be stored away from excess heat and moisture, at room temperature. If you have any questions, ask your doctor or pharmacist. You will prevent a lot of problems and you can also find useful details.