WebMD Ask the Pharmacist

Drug Safety and Drug Interactions: Ask the Pharmacist

March 16, 2010. Pharmacist Heather Free, PharmD, answers questions about drug safety and drug interactions.

Question:

My husband has been taking Janumet for diabetes. Now the insurance company wants him to ask his doctor about cheaper medicine. What do you suggest? And why do this now when he has been taking Janumet for a year?

Answer:

Janumet is a combination product containing Januvia and metformin. Both medications are used to help decrease sugar levels found in blood circulation after eating a meal, but by different mechanisms of actions. Metformin is a generic medication that can be found at several pharmacies on their special pricing lists for one month and three month supplies. However, Januvia is still a brand medication, as well as Janumet.

There are plenty of different combinations of diabetes medications that can be used to lower sugar levels. However, if sugar levels are being maintained with this combination product, I would not switch. Check with your insurance company to see if there is a lower co-pay for using Januvia versus Janumet. If so, you still can get the same coverage as Janumet by taking the two ingredients, Januvia and metformin. There aren’t medications in the same drug class, but there are medications available to help lower sugar levels by a different means of action within the body. Start by contacting your insurance to see what they cover and at what co-pay costs. Work with your pharmacist and physician to see what will work best for diabetes coverage specific to your husband’s needs. Check around with pharmacies to see if they have different generic lists of medications they cover at a lower cost that may be lower than your insurance.

Lastly, talk to your doctor to see if he/she has any co-pay assistance cards. Many brand medications do have an assistance program to aid with co-pays. If you got the company’s web site (www.janumet.com) you can download coupons and sign up for their program.

Question:

I caught a cold, I have 100.4 degree fever, and I am planning to take Boniva tomorrow. Can I take Tylenol to reduce fever with Boniva?

Answer:

Tylenol and Boniva are safe to take together or at different intervals throughout the day. However, there are a few medications you should not take or should alter the time you take the doses while taking Boniva.

Aspirin/NSAIDs can easily, without one knowing, damage the gastrointestinal (GI) tract, causing irritation and possible bleeding. Boniva is also very irritating to the GI system. Therefore, to reduce the irritation to the GI, the medications should not be used adjunctively. Remember, there are over-the-counter NSAIDs as well as prescription NSAIDs. If an NSAID medication is required for another indication than fever, timing is important.

Spread out the dose of Boniva from the NSAID. Remember to take Boniva on an empty stomach and the NSAID with food, even if you do not feel stomach irritation. Work with your pharmacist and/or health care provider about timing and evaluating whether both medications should be maintenance therapy.

Boniva has a drug interaction with calcium supplements and antacids. These products can decrease the absorption of Boniva, decreasing the effects of the medication. It is not that you cannot take these products, but rather about the timing. Take Boniva 60 minutes, on an empty stomach, prior to taking any calcium supplements and antacids.

Question:

I am now taking gemfibrozil and I find it very hard to take this medication 30 minutes before breakfast and dinner. I take other drugs and vitamins and I forget to take this drug on a daily basis. I take Diltzac, Evista, and Nexium. I also take vitamins which include a multivitamin, calcium, vitamin D, fish oil, biotin and CoQ10. Do any of these interact with gemfibrozil?

Answer:

The medications that you are taking do not interact with gemfibrozil. However, if you are looking for a better schedule for taking your medications, preventing any drug interactions, I would separate out the Nexium from the group. Nexium can decrease the absorption of some vitamins and minerals, more specifically the calcium. Calcium is better absorbed in an acidic environment. Take the Nexium in the morning on an empty stomach by itself. Later, with breakfast take the multivitamin, calcium, vitamin D, fish oil, biotin and CoQ10 (at least 60 minutes later). Diltzac and Evista should be taken per frequency prescribed by your physician and may be taken with or without food.

Question:

Can you go in the sun if you’re taking isotretinoin?

Answer:

You should not expose yourself to the sun without using sunscreen while being on isotretinoin. Isotretinoin is a photosensitive medication, making you more susceptible to sunburns and cancer.

Question:

What is the drug interaction between ceftizoxime and gentamicin?

Answer:

I’m not sure which cephalosporin this patient is asking about. Cephalosporins, given with gentamicin, may increase the risk of nephrotoxicity. I would check with your pharmacist before taking the combination so he/she can contact your doctor for a better explanation of the use of both medications together. Depending on which cephalosporin is being used with gentamicin, the risk of nephrotoxicity increases. The risks vs. the benefits need to be determined. So work with your pharmacist to determine the need for both antibiotics, or to determine whether or not there is another antibiotic combination available that is more suitable for you.

Question:

What is the difference between valproic acid and sodium valproate?

Answer:

Valproic acid is a substrate that the body converts to the active form, valproate. Both Valproic acid and valproate are used to help decrease seizures within the body. You may see both of these names when looking at a package insert or reading information about the drug.

Question:

What is the difference between the medicines Nexium and Kapidex?

Answer:

Nexium and Kapidex (now called Dexilant) are both within the same drug class. They are proton pump inhibitors, which aid in the decrease of acid production to prevent and/or treat GERD and certain ulcers. They are made by different companies but work very similarly, having similar drug interactions and side effect profiles.

Question:

I had a question about taking Lasix and having allergies to sulfur drugs. Why would it be OK to take Lasix?

Answer:

If you have a true allergy to sulfa medications then Lasix may not be for you. It does contain sulfa product. If you have difficulty breathing, or your airways feel like they are closing off, or a rash has developed, specifically on the trunk of the body, then you should stop taking this medication immediately and consult with your pharmacist and health care provider.

It is important to differentiate between allergies to medications and side effects. If you have experienced intolerable side effects to medications containing sulfa products, that doesn’t mean you are allergic. Work with you local pharmacist and physician to re-evaluate this situation and to make sure you are taking medication that is appropriate for you.

Question:

Can I take Alka-Seltzer if I am taking Nexium?

Answer:

It is important to look at the Alka-Seltzer box and identify the active ingredients found in the product. Assuming that you are inquiring about the regular Alka-Seltzer, this product would be all right to take, but I would still recommend that you take them separately, meaning at different times.

Question:

If I took a hydrochlorothiazide in the morning at 6 and a metoprolol tonight at 12, is that too close to the metoprolol?

Answer:

The two medications that you are taking are both blood pressure medications that work different ways to help lower your blood pressure. Hydrochlorothiazide is best to take in the morning to help with diuresis during the day rather than night when you are trying to sleep. Metoprolol is a beta-blocker that can cause drowsiness, dizziness, or impaired thinking. All these side effects may wear off by the time you wake up in the morning. Therefore, taking it at night before bed may be best for you.

How you are taking the medication is fine, since they both work in different ways to help control your blood pressure. Just watch for hypotensive effects or dizziness in the morning when you’re trying to get out of bed. If this occurs, you may want to take the metoprolol earlier than midnight. You should also monitor your pulse to make sure it doesn’t get too low. Consult your pharmacist and health care provider if any of these symptoms persist.

Question:

Does Monistat contain aspirin or ibuprofen?

Answer:

Monistat is an antifungal medication and doesn’t contain any aspirin or ibuprofen.

Question:

Is it OK to take Plavix with Zantac?

Answer:

Plavix does not have a direct interaction with Zantac. However, if you have a history of ulcers, or if you are being treated for ulcers, you should consult your health care provider before taking Plavix. If you are just using Zantac for a temporary relief of indigestion, these two medications should be fine to take together.

Question:

Is oxybutynin in the family with diazepam?

Answer:

Oxybutynin is a medication used for overactive bladder and urinary tract spasms. It is not in the same class or family as diazepam (benzodiazepine class). They work differently and have different indications.

Question:

Is Avinza a narcotic medication?

Answer:

Avinza is the extended release formulation of morphine sulfate. Due to the addictive properties associated with this medication it is classified as a narcotic or schedule II medication.

Question:

Can ibuprofen or aspirin be taken with steroids?

Answer:

Great question! It is important to watch what over-the-counter medications are taken with prescription medications. Steroids, such as prednisone, can be harsh on the stomach. The same holds true with ibuprofen. If it is for temporary use, separate out the doses and take with food.

Aspirin and prednisone have a mild drug interaction and is more of a concern when tapering or taking someone off steroid therapy. Always consult your pharmacist or health care provider with your specific request and to discuss the reasons you want to use the combination of therapy before using it.

Question:

Is there a generic form of Plavix or Coreg?

Answer:

Plavix does not have a generic currently on the market and can have a rather expensive co-pay. For co-pay assistance, check with the Plavix main web site for coupons and programs to aid in the cost. However, Coreg does have a generic otherwise known as carvedilol. The co-pay for the generic medication can be considerably less expensive and some pharmacies have this medication on their special pricing list, which could make it even more affordable.

Question:

Can I take Mucinex with Zoloft?

Answer:

There has not been any interaction reported with Mucinex and Zoloft. You should be fine taking these two medications together. Always consult your pharmacist and health care provider to make sure that there are no known interactions.

Question:

I'm taking Adderall daily, citalopram daily, Klonopin occasionally (if can't sleep), and I was just prescribed Grifulvin V micr 500 tablets for a recently diagnosed case of ringworm of the body, scalp, feet, and facial areas. So, is Adderall + citalopram + Klonopin + Grifulvin 500 tablets a safe combination?

Answer:

This combination of medications does not have any drug interactions. However, I would take the Grifulvin with food to minimize the stomach irritation and with a fatty substance, like milk or yogurt. A fatty substance will help to increase the absorption of the medication to effectively treat the condition. Do not skip any doses and you may have to complete therapy for 6 weeks in order to eradicate the condition.

Question:

Can I take Cymbalta with triamterene without an interaction?

Answer:

There is a moderate drug interaction between these two medications that may cause an increased occurrence of orthostatic hypotension (blood pressure suddenly falls when standing up) that subsides within two weeks of initiating adjunctive therapy. Hyponatremia (low sodium) has also been seen in some cases.

If you begin to experience potential signs and symptoms of hyponatremia, such as headache, difficulty concentrating, memory impairment, confusion, weakness, and unsteadiness (which may lead to falls), you should consult your health care provider and pharmacist.

This doesn’t mean that you cannot take these two medications together. Work closely with your health care provider or pharmacist in monitoring yourself for any side effects associated with the drug interactions. Risks and benefits should be weighed in this situation to make sure the therapy is the correct therapy for you.

Question:

How do atenolol and Premarin interact with each other?

Answer:

There are not drug interactions reported between these two medications and should be all right to take together. Always consult your health care provider and pharmacist to make sure that no interactions continue to exist.

Question:

What is the difference between Augmentin and amoxicillin?

Answer:

Augmentin is a combination product containing amoxicillin and clavulanate potassium. This medication was designed to help reduce the drug resistance seen with bacteria when just amoxicillin was used alone. The selection of the antibiotic is done by evaluating the type of bacteria that is present, and the common treatments that have been effective in treating the infection. Side effect profiles and drug interactions are similar. Remember, if you are allergic to amoxicillin, you will be allergic to Augmentin.

Question:

Can I take Elavil and Tylenol together?

Answer:

There are not drug interactions reported between these two medications and should be all right to take together. Always consult your health care provider and pharmacist to make sure that no interactions continue to exist.

Question:

Can Paxil 30 mg, Geodon 80 mg, and Dilantin 100 mg taken for seizures be taken at the same time?

Answer:

These medications have minor drug interactions that I am sure your physician is monitoring. It is safe to take these medications together and I have seen this combination many times. Dilantin can decrease the concentrations of Geodon. This may explain why a higher dose is being used in your situation. Remember, all of the medications can cause dizziness, drowsiness, and may impair your normal functioning, causing an additive effect. Just limit your activities until you are better accustomed to the side effects, or until the side effects begin to decrease. Work with your pharmacist and health care provider, especially if the side effects are too much for you.

Question:

If I take amlodipine in the morning, can I take Viagra at night?

Answer:

Yes, taking the medication spread out will decrease the possibility of hypotension symptoms, such as dizziness, lightheadedness, or fainting. This is typically seen with co-administration and should be avoided. Do not take the medications together. Since you would be taking the medications at different intervals you should be fine.


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