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Drug Interactions between 5-hydroxytryptophan / melatonin / pyridoxine and isoniazid

This report displays the potential drug interactions for the following 2 drugs:

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Interactions between your drugs

Moderate

isoniazid melatonin

Applies to: isoniazid and 5-hydroxytryptophan / melatonin / pyridoxine

Consumer information for this interaction is not currently available.

MONITOR: Coadministration with inhibitors of CYP450 1A2 may substantially increase the plasma concentrations of melatonin. Data from available studies suggest that melatonin is primarily metabolized by CYP450 1A2, with possible contribution from CYP450 2C19 and 2C9. Coadministration of fluvoxamine, a potent CYP450 1A2 inhibitor that also inhibits CYP450 2C19 and 2C9, increased melatonin systemic exposure (AUC) by 17-fold and maximum plasma concentration (Cmax) by 12-fold. Contraceptives containing ethinyl estradiol, which can inhibit CYP450 1A2, may lead to a 4- to 5-fold increase in melatonin concentration. The risk of this interaction may be less likely to occur with estrogen products that have limited systemic absorption (e.g., vaginal, topical products).

MANAGEMENT: Caution is advised when melatonin is used concomitantly with CYP450 1A2 inhibitors. Patients should be monitored closely for adverse effects such as excessive drowsiness, headache, lethargy, dizziness, irritability, nervousness, restlessness, anxiety, abdominal pain, and dyspepsia.

Moderate

isoniazid 5-hydroxytryptophan

Applies to: isoniazid and 5-hydroxytryptophan / melatonin / pyridoxine

If you are currently being treated with 5-hydroxytryptophan, let your doctor know before you receive isoniazid. Combining these medications can increase the risk of a rare but serious condition called the serotonin syndrome, which may include symptoms such as confusion, hallucinations, seizure, extreme changes in blood pressure, increased heart rate, fever, excessive sweating, shivering or shaking, blurred vision, muscle spasm or stiffness, tremor, incoordination, stomach cramps, nausea, vomiting, and diarrhea. Talk to your doctor if you have any questions or concerns. Your doctor may be able to prescribe alternatives that do not interact. 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

Moderate

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.

Moderate

melatonin food

Applies to: 5-hydroxytryptophan / melatonin / pyridoxine

Both smoking and excessive caffeine consumption can alter the blood levels of melatonin, which may affect the dosing. Tobacco smoking reduces, while caffeine increases melatonin blood levels. If you start smoking or undergo smoking cessation, your doctor may need to adjust the dose of melatonin. In addition, alcohol may reduce the effect of melatonin on sleep. It is best to avoid alcohol consumption during melatonin therapy. Talk to a healthcare professional if you have any questions or concerns. 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.


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Drug Interaction Classification

These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.
Major Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit.
Moderate Moderately clinically significant. Usually avoid combinations; use it only under special circumstances.
Minor 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.
Unknown No interaction information available.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.