Janumet Drug Interactions

Janumet Drug Interactions
eMedTV.com
Written by/reviewed by: Kristi Monson, PharmD; Arthur Schoenstadt, MD Last reviewed by: Kristi Monson, PharmD;

A number of medications should not be taken with Janumet. Drug interactions may occur if the combination diabetes medication is taken with calcium channel blockers, corticosteroids, diuretics, or estrogens. These interactions can decrease the effectiveness of Janumet, which can increase your risk of developing high blood sugar. If Janumet drug interactions are a concern, your healthcare provider may adjust your dosages.

An Overview of Janumet Drug Interactions
Janumet? (sitagliptin and metformin) may potentially interact with a number of other medicines. Some of these medicines that may lead to Janumet drug interactions include:

* Certain decongestants, such as phenylephrine (Sudafed PE?) or psuedoephedrine (Sudafed?)

* Calcium channel blockers, such as:
o Amlodipine (Norvasc?)
o Diltiazem (Cardizem?, Dilacor?, Tiazac?)
o Felodipine (Plendil?)
o Isradipine (DynaCirc?)
o Nicardipine (Cardene?)
o Nifedipine (Adalat?, Procardia?)
o Nisoldipine (Sular?)
o Verapamil (Calan?, Verelan?)

* Cimetidine (Tagamet?)

* Corticosteroids, such as:
o Betamethasone (Celestone?)
o Cortisone
o Dexamethasone (Decadron?)
o Fludrocortisone (Florinef?)
o Hydrocortisone (Cortef?)
o Methylprednisolone (Depo-Medrol?, Medrol?)
o Prednisolone (Ovapred?, Pediapred?)
o Prednisone
o Triamcinolone (Kenalog?, Aristospan?)

* Digoxin (Digitek?, Lanoxin?)

* Diuretics, such as:
o Acetazolamide (Diamox?)
o Amiloride (Midamor?)
o Bumetanide (Bumex?)
o Chlorothiazide (Diuril?)
o Chlorthalodone
o Ethacrynic acid (Edecrin?)
o Furosemide (Lasix?)
o Hydrochlorothiazide (Microzide?, HCTZ)
o Metolazone (Zaroxolyn?)
o Torsemide (Demadex?)
o Triamterene (Dyrenium?, Dyazide?, Maxzide?)

* Estrogens

* Isoniazid

* Niacin (nicotinic acid, Niaspan?, Niacor?, Nicolar?)

* Oral contraceptives (birth control pills)

* Phenothiazine medications, including:
o Chlorpromazine
o Fluphenazine (Prolixin?)
o Perphenazine
o Promethazine (Phenergan?)
o Thioridazine (Mellaril?)
o Trifluoperazine

* Phenytoin (Dilantin?)

* Thyroid medications, such as levothyroxine (Levothroid?, Levoxyl?, Synthroid?, Unithroid?), liothryonine (Cytomel?), thyroid (Armour Thyroid?), and Thyrolar?.

Janumet Interactions Explained
The following sections explain in detail the potentially negative interactions that can occur when Janumet is combined with any of the drugs listed above.

Certain Decongestants
Taking Janumet with certain decongestants can make Janumet less effective, potentially increasing your chance of high blood sugar (hyperglycemia). Decongestants are in many cough and cold products, so be sure to talk to your healthcare provider before taking any cough or cold medications during treatment with Janumet.

Calcium Channel Blockers
Combining Janumet with calcium channel blockers can make Janumet less effective, which may increase your risk of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping a calcium channel blocker.

However, taking Janumet with nifedipine (a calcium channel blocker) can also increase the level of Janumet in your blood. Your healthcare provider may need to adjust your dose of Janumet in this situation to prevent interactions from occurring.

Cimetidine
Taking Janumet with cimetidine can increase the level of Janumet in your blood, possibly increasing your risk of side effects. Your healthcare provider may need to adjust your dose of these medications or suggest an alternative to cimetidine, depending on your particular situation.

Corticosteroids
If Janumet is taken with corticosteroids, it can make Janumet less effective, increasing your chance of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping a corticosteroid.

Digoxin
Taking digoxin and Janumet together may affect the level of both medications in your blood. Your healthcare provider should monitor the level of digoxin in your blood, especially when starting or stopping Janumet.

Diuretics
Combining Janumet with diuretics can make Janumet less effective, potentially increasing your risk of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping a diuretic.

Taking Janumet with furosemide (a diuretic) can affect the levels of both medications in your blood. This may increase your risk of Janumet side effects and make furosemide less effective. Your healthcare provider may need to adjust your dose of these medications to prevent drug interactions from occurring.

Estrogens
If Janumet is combined with estrogens, it can make Janumet less effective, potentially increasing your chance of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping an estrogen.

Isoniazid
Taking Janumet with isoniazid can make Janumet less effective, increasing your chance of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping isoniazid.

Niacin
Combining Janumet with niacin can make Janumet less effective, possibly increasing your chance of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping niacin.

Oral Contraceptives
Taking Janumet with oral contraceptives (birth control pills) can make Janumet less effective, which may increase your chance of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping an oral contraceptive.

Phenothiazines
Combining Janumet with phenothiazines can make Janumet less effective, possibly increasing your risk of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping a phenothiazine.

Phenytoin
If Janumet is taken with phenytoin, it can make Janumet less effective, increasing your chance of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping a phenytoin.

Thyroid Medications
Taking Janumet with thyroid medications can make Janumet less effective, potentially increasing your chance of high blood sugar (hyperglycemia). You may need to be monitored more closely, and your healthcare provider may need to adjust your Janumet dose, especially when starting or stopping a thyroid medication.

Final Thoughts on Janumet Drug Interactions
It is possible that not all Janumet drug interactions were discussed in this article. Therefore, you should talk with your pharmacist or healthcare provider about the specific drug interactions that may apply to you.

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