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Drug interactions between ampicillin and methotrexate

Results for the following 2 drugs:

Interactions between your drugs


ampicillin ↔ methotrexate

Applies to:ampicillin and methotrexate

Talk to your doctor before using methotrexate together with ampicillin. Medications like ampicillin, especially when given at high dosages for serious infections, can sometimes increase the blood levels and effects of methotrexate. You may have increased side effects such as nausea, vomiting, mouth ulcers, and low blood cell counts, which can make you more likely to develop anemia, bleeding problems, and infections. Contact your doctor if you experience potential signs and symptoms of these conditions such as paleness, fatigue, dizziness, fainting, unusual bleeding or bruising, fever, chills, sore throat, body aches, or other flu-like symptoms. You may need a dose adjustment or more frequent monitoring by your doctor 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.

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Drug and food interactions


methotrexate food

Applies to: methotrexate

Caffeine may reduce the effectiveness of methotrexate in the treatment of arthritis. If you are receiving methotrexate for arthritis, you may want to limit your intake of caffeine-containing foods and medications. Check with your doctor or pharmacist if you have concerns or are uncertain what products may contain caffeine.

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ampicillin food

Applies to: ampicillin

You may experience reduced absorption of ampicillin in the presence of food. The effectiveness of the antibiotic may be reduced. Ampicillin should be administered one hour before or two hours after meals. This will make it easier for your body to absorb the medication. Penicillin V and amoxicillin are not affected by food and may be given without regard to meals.

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Therapeutic duplication warnings

No therapeutic duplications were found for your selected drugs.

Drug Interaction Classification

The classifications below are a guideline only. The relevance of a particular drug interaction to a specific patient is difficult to determine using this tool alone given the large number of variables that may apply.
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 information available.

Do not stop taking any medications without consulting your healthcare provider.

Disclaimer: Every effort has been made to ensure that the information provided by Multum is accurate, up-to-date and complete, but no guarantee is made to that effect. In addition, the drug information contained herein may be time sensitive and should not be utilized as a reference resource beyond the date hereof. This material does not endorse drugs, diagnose patients, or recommend therapy. Multum's information is a reference resource designed as supplement to, and not a substitute for, the expertise, skill, knowledge, and judgement of healthcare practitioners in patient care. The absence of a warning for a given drug or combination thereof in no way should be construed to indicate that the drug or combination is safe, effective, or appropriate for any given patient. Multum Information Services, Inc. does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. Copyright 2000-2018 Multum Information Services, Inc. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse, or pharmacist.