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Drug Interaction Report

This report displays the potential drug interactions for the following 11 drugs:

  • Ambien (zolpidem)
  • Synthroid (levothyroxine)
  • Premarin (conjugated estrogens)
  • clonazepam
  • omeprazole
  • famotidine
  • MiraLAX (polyethylene glycol 3350)
  • fluticasone nasal
  • cetirizine
  • Vitamin D3 (cholecalciferol)
  • venlafaxine

Edit list (add/remove drugs)

Interactions between your drugs

Moderate

clonazePAM omeprazole

Applies to: clonazepam, omeprazole

Omeprazole may increase the blood levels and effects of clonazePAM. This can increase the risk of side effects including excessive drowsiness and breathing difficulties. 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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Moderate

levothyroxine omeprazole

Applies to: Synthroid (levothyroxine), omeprazole

Taking levothyroxine with omeprazole may interfere with the absorption of levothyroxine and reduce its effectiveness. Contact your doctor if you experience signs and symptoms of reduced thyroid function such as fatigue; sluggishness; constipation; depression; hoarseness; unexplained weight gain; sensitivity to cold; pale, dry skin; muscle aches, weakness, or tenderness; joint pain, stiffness, or swelling; heavier than normal menstruation periods; or brittle fingernails and hair. 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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Moderate

levothyroxine conjugated estrogens

Applies to: Synthroid (levothyroxine), Premarin (conjugated estrogens)

Before taking conjugated estrogens, tell your doctor if you also use levothyroxine. You may need dose adjustments or special tests in order to safely take both medications together. If you are already taking conjugated estrogens and levothyroxine, your thyroid levels may need to be measured if your dose of conjugated estrogens is changed or stopped. You should notify your doctor if you have symptoms of low thyroid such as tiredness, feeling cold, constipation, unexplained weight gain, depression, joint or muscle pain, thinning hair or hair loss, dry skin, hoarseness, and abnormal menstrual periods. 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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Moderate

clonazePAM zolpidem

Applies to: clonazepam, Ambien (zolpidem)

Using clonazePAM together with zolpidem may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. Talk to your doctor 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.

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Moderate

famotidine venlafaxine

Applies to: famotidine, venlafaxine

Using famotidine together with venlafaxine can increase the risk of an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect. You may be more susceptible if you have a heart condition called congenital long QT syndrome, other cardiac diseases, conduction abnormalities, or electrolyte disturbances (for example, magnesium or potassium loss due to severe or prolonged diarrhea or vomiting). Talk to your doctor if you have any questions or concerns. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications, whether together or alone. 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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Moderate

clonazePAM venlafaxine

Applies to: clonazepam, venlafaxine

Using clonazePAM together with venlafaxine may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. Talk to your doctor 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.

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Moderate

zolpidem venlafaxine

Applies to: Ambien (zolpidem), venlafaxine

Using zolpidem together with venlafaxine may increase side effects such as dizziness, drowsiness, confusion, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medications affect you. Talk to your doctor 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.

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Moderate

clonazePAM cetirizine

Applies to: clonazepam, cetirizine

Using cetirizine together with clonazePAM may increase side effects such as dizziness, drowsiness, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid driving, operating machinery, or engaging in potentially hazardous activities requiring mental alertness and motor coordination until you know how the medications affect you. Talk to your doctor 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.

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Moderate

venlafaxine cetirizine

Applies to: venlafaxine, cetirizine

Using cetirizine together with venlafaxine may increase side effects such as dizziness, drowsiness, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid driving, operating machinery, or engaging in potentially hazardous activities requiring mental alertness and motor coordination until you know how the medications affect you. Talk to your doctor 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.

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Moderate

zolpidem cetirizine

Applies to: Ambien (zolpidem), cetirizine

Using cetirizine together with zolpidem may increase side effects such as dizziness, drowsiness, and difficulty concentrating. Some people, especially the elderly, may also experience impairment in thinking, judgment, and motor coordination. You should avoid or limit the use of alcohol while being treated with these medications. Also avoid driving, operating machinery, or engaging in potentially hazardous activities requiring mental alertness and motor coordination until you know how the medications affect you. Talk to your doctor 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.

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Moderate

venlafaxine polyethylene glycol 3350

Applies to: venlafaxine, MiraLAX (polyethylene glycol 3350)

Venlafaxine can cause an irregular heart rhythm that may be serious and potentially life-threatening, although it is a relatively rare side effect. The risk is increased if you have low blood levels of magnesium or potassium, which can occur with bowel cleansing preparations or excessive use of medications that have a laxative effect. Do not exceed the dose and duration of use of polyethylene glycol 3350 recommended on the product label or prescribed by your doctor. You should seek immediate medical attention if you develop sudden dizziness, lightheadedness, fainting, shortness of breath, or heart palpitations during treatment with these medications. In addition, you should let your doctor know if you experience signs and symptoms of low magnesium or potassium blood level such as weakness, tiredness, drowsiness, dizziness, confusion, tingling, numbness, muscle pain, cramps, nausea, or vomiting. 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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No other interactions were found between your selected drugs. This does not necessarily mean no other interactions exist. Always consult your healthcare provider.

Drug and food interactions

Moderate

levothyroxine food

Applies to: Synthroid (levothyroxine)

The timing of meals relative to your levothyroxine dose can affect absorption of the medication. Therefore, levothyroxine should be taken on a consistent schedule with regard to time of day and relation to meals to avoid large fluctuations in blood levels, which may alter its effects. In addition, absorption of levothyroxine may be decreased by foods such as soybean flour, cotton seed meal, walnuts, dietary fiber, calcium, and calcium fortified juices. These foods should be avoided within several hours of dosing if possible. 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 levothyroxine is given during continuous enteral nutrition (tube feedings) for more than 7 days, the tube feeding should be interrupted for at least one hour before and one hour after the dose of levothyroxine. You may need more frequent blood tests to monitor levothyroxine levels.

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Moderate

zolpidem food

Applies to: Ambien (zolpidem)

You should avoid the use of alcohol while being treated with zolpidem. Alcohol can increase the nervous system side effects of zolpidem such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. Taking zolpidem with food may delay the onset of sleep. For faster sleep onset, zolpidem should not be taken with or immediately after a meal. This will make it easier for your body to absorb the medication. Talk to your doctor or pharmacist if you have any questions or concerns.

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Moderate

cetirizine food

Applies to: cetirizine

Alcohol can increase the nervous system side effects of cetirizine such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with cetirizine. Do not use more than the recommended dose of cetirizine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

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Moderate

venlafaxine food

Applies to: venlafaxine

Alcohol can increase the nervous system side effects of venlafaxine such as dizziness, drowsiness, and difficulty concentrating. Some people may also experience impairment in thinking and judgment. You should avoid or limit the use of alcohol while being treated with venlafaxine. Do not use more than the recommended dose of venlafaxine, and avoid activities requiring mental alertness such as driving or operating hazardous machinery until you know how the medication affects you. Talk to your doctor or pharmacist if you have any questions or concerns.

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Minor

conjugated estrogens food

Applies to: Premarin (conjugated estrogens)

Consumer information for this minor interaction is not currently available. Some minor drug interactions may not be clinically relevant in all patients. Minor drug interactions do not usually cause harm or require a change in therapy. However, your healthcare provider can determine if adjustments to your medications are needed.

For clinical details see professional interaction data.

Therapeutic duplication warnings

Therapeutic duplication is the use of more than one medicine from the same drug category or therapeutic class to treat the same condition. This can be intentional in cases where drugs with similar actions are used together for demonstrated therapeutic benefit. It can also be unintentional in cases where a patient has been treated by more than one doctor, or had prescriptions filled at more than one pharmacy, and can have potentially adverse consequences.

Duplication

Acid suppressant agents

Therapeutic duplication

The recommended maximum number of medicines in the 'acid suppressant agents' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'acid suppressant agents' category:

  • omeprazole
  • famotidine

Note: The benefits of taking this combination of medicines may outweigh any risks associated with therapeutic duplication. This information does not take the place of talking to your doctor. Always check with your healthcare provider to determine if any adjustments to your medications are needed.

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.

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