Drug Interactions between isoniazid and theophylline
This report displays the potential drug interactions for the following 2 drugs:
- isoniazid
- theophylline
Interactions between your drugs
isoniazid theophylline
Applies to: isoniazid and theophylline
Using isoniazid together with theophylline can increase the effects of theophylline. You should contact your doctor if you experience nausea, vomiting, diarrhea, headache, restlessness, insomnia, seizures, or an irregular heartbeat. You may need a dose adjustment or special test to safely use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
Drug and food interactions
isoniazid food
Applies to: isoniazid
Food can decrease the levels of isoniazid in your body. Taking isoniazid on an empty stomach (at least 30 minutes before or 2 hours after a meal) will make it easier for your body to absorb the medication. Avoid drinking alcohol while taking isoniazid because alcohol use may increase the risk of damage to your liver and your risk of experiencing a condition known as peripheral neuropathy (i.E., weakness, numbness, and pain typically in the hands and feet). Your doctor may advise you to take a vitamin B6 (pyridoxine) supplement during your treatment to help prevent peripheral neuropathy. Isoniazid may interact with foods containing histamine or tyramine (e.G., aged cheese, cured meats such as sausages and salami, fava beans, sauerkraut, soy sauce, beer, red wine, skipjack, tuna, mackerel, salmon), which can cause symptoms like headache, sweating, flushing, palpitations, dizziness, lightheadedness, or feeling faint. These foods should generally be avoided. It is important to seek immediate medical care if you experience any severe side effects or symptoms of liver damage such as fever, chills, joint pain or swelling, unusual bleeding or bruising, skin rash, itching, loss of appetite, fatigue, nausea, vomiting, dark colored urine, and/or yellowing of the skin or eyes. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
theophylline food
Applies to: theophylline
Both smoking and excessive caffeine consumption can alter the blood levels of theophylline, which may affect the dosing. Tobacco and marijuana smoke (including secondhand exposure) generally reduces, while caffeine increases, blood levels. In addition, caffeine is a stimulant and may add to the side effects of theophylline such as headache, insomnia, and increases in blood pressure and heart rate. It is best to avoid smoking and to limit caffeine consumption during theophylline therapy. Talk to a healthcare professional if you have any questions or concerns. If you start smoking or undergo smoking cessation, your doctor may need to monitor your blood levels more closely to determine if you need a dose adjustment of theophylline. You should stop taking theophylline and seek medical attention if you experience potential signs and symptoms of excessive drug levels such as nausea, vomiting, persistent headache, insomnia, and rapid heartbeat. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
When theophylline is given with enteral (tube) feedings, blood levels may be decreased due to interference with its absorption. This may reduce the effectiveness of the medication. To minimize potential for interaction, you may interrupt the feeding for one hour before and one hour after the theophylline dose. You may need more frequent blood tests to monitor theophylline levels.
theophylline food
Applies to: theophylline
Ask your doctor before using theophylline together with caffeine. Using these medications together may increase some of the side effects of theophylline. This can cause nausea, vomiting, insomnia, tremors, restlessness, uneven heartbeats, and seizure (convulsions). Avoid drinks or foods that contain caffeine, such as coffee, tea, cola, and chocolate. You may need a dose adjustment or special test if you use both medications. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.
Therapeutic duplication warnings
No warnings were found for your selected drugs.
Therapeutic duplication warnings are only returned when drugs within the same group exceed the recommended therapeutic duplication maximum.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
Minimally clinically significant. Minimize risk; assess risk and consider an alternative drug, take steps to circumvent the interaction risk and/or institute a monitoring plan. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
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