Drug Interactions between losartan and Purinethol
This report displays the potential drug interactions for the following 2 drugs:
- losartan
- Purinethol (mercaptopurine)
Interactions between your drugs
No interactions were found between losartan and Purinethol. However, this does not necessarily mean no interactions exist. Always consult your healthcare provider.
losartan
A total of 319 drugs are known to interact with losartan.
- Losartan is in the drug class angiotensin receptor blockers.
- Losartan is used to treat the following conditions:
Purinethol
A total of 280 drugs are known to interact with Purinethol.
- Purinethol is in the drug class antimetabolites.
- Purinethol is used to treat Acute Lymphoblastic Leukemia.
Drug and food interactions
mercaptopurine food
Applies to: Purinethol (mercaptopurine)
ADJUST DOSING INTERVAL: Limited data suggest that food may decrease the oral bioavailability of 6-mercaptopurine (6-MP). In one study, the pharmacokinetics of 6-MP were studied on two separate occasions in seven patients. A single dose of 6-MP was administered after an overnight fast on one occasion and 15 minutes after a standard breakfast on the other. The authors reported that peak plasma levels of 6-MP were lower and took longer to reach following administration in the fed state. In addition, plasma levels were undetectable (less than 20 ng/mL) in two patients.
MANAGEMENT: Until more information is available regarding the effect of food on 6-MP absorption, it may be advisable to take 6-MP on an empty stomach 1 hour before or 2 hours after a meal.
References
- Schmidt LE, Dalhoff K (2002) "Food-drug interactions." Drugs, 62, p. 1481-502
losartan food
Applies to: losartan
GENERALLY AVOID: Moderate-to-high dietary intake of potassium, especially salt substitutes, may increase the risk of hyperkalemia in some patients who are using angiotensin II receptor blockers (ARBs). ARBs can promote hyperkalemia through inhibition of angiotensin II-induced aldosterone secretion. Patients with diabetes, heart failure, dehydration, or renal insufficiency have a greater risk of developing hyperkalemia.
MANAGEMENT: Patients should receive dietary counseling and be advised to not use potassium-containing salt substitutes or over-the-counter potassium supplements without consulting their physician. If salt substitutes are used concurrently, regular monitoring of serum potassium levels is recommended. Patients should also be advised to seek medical attention if they experience symptoms of hyperkalemia such as weakness, irregular heartbeat, confusion, tingling of the extremities, or feelings of heaviness in the legs.
MONITOR: Grapefruit juice may modestly decrease and delay the conversion of losartan to its active metabolite, E3174. The proposed mechanism is inhibition of CYP450 3A4-mediated first-pass metabolism in the gut wall by certain compounds present in grapefruits. The clinical significance is unknown. Moreover, pharmacokinetic alterations associated with interactions involving grapefruit juice are often subject to a high degree of interpatient variability.
MANAGEMENT: Patients who regularly consume grapefruits and grapefruit juice should be monitored for altered efficacy of losartan. Grapefruits and grapefruit juice should be avoided if an interaction is suspected. Orange juice is not expected to interact.
References
- (2001) "Product Information. Cozaar (losartan)." Merck & Co., Inc
- Zaidenstein R, Soback S, Gips M, Avni B, Dishi V, Weissgarten Y, Golik A, Scapa E (2001) "Effect of grapefruit juice on the pharmacokinetics of losartan and its active metabolite E3174 in healthy volunteers." Ther Drug Monit, 23, p. 369-73
- Ray K, Dorman S, Watson R (1999) "Severe hyperkalaemia due to the concomitant use of salt substitutes and ACE inhibitors in hypertension: a potentially life threatening interaction." J Hum Hypertens, 13, p. 717-20
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.
See also
Drug Interaction Classification
Highly clinically significant. Avoid combinations; the risk of the interaction outweighs the benefit. | |
Moderately clinically significant. Usually avoid combinations; use it only under special circumstances. | |
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. | |
No interaction information available. |
Further information
Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.
Check Interactions
To view an interaction report containing 4 (or more) medications, please sign in or create an account.
Save Interactions List
Sign in to your account to save this drug interaction list.