Pioglitazone with Bitter Melon Interaction Details

Brand Names Associated with Pioglitazone

Medical Content Editor Dr. Brian Staiger, PharmD
Last updated Dec 02, 2023

Interaction Effect

Increased risk of hypoglycemia

Interaction Summary

Bitter melon significantly reduced blood glucose in patients with diabetes in clinical trials. A case has been reported in which a patient's chlorpropamide dose was decreased due to bitter melon intake, based on urinary glucose measurements , but this has been questioned as bitter melon may produce false negative results on urine glucose test strips . It is postulated that bitter melon exerts its hypoglycemic effect through hepatic or peripheral glucose disposal . Insulin levels remained unchanged . Theoretically, concomitant use of bitter melon with antidiabetic agents may result in additive reductions in blood glucose. This may predispose some patients to hypoglycemic reactions (manifested as blurred vision, tremor, intense hunger, generalized sweating, headache, palpitations, piloerection, lethargy, confusion, nervousness, and agitation).

Severity

Moderate

Onset

Rapid

Evidence

Probable

How To Manage Interaction

If bitter melon and an antidiabetic agent are used together, blood glucose levels should be monitored regularly. Theoretically, concomitant use of bitter melon with hypoglycemic medications may result in additive reductions in blood glucose. This may predispose some patients to hypoglycemic reactions (manifested as blurred vision, tremor, intense hunger, generalized sweating, headache, palpitations, piloerection, lethargy, confusion, nervousness, and agitation). Different forms of bitter melon (extract, juice, fruit, dried fruit) appear to have variable effects on blood glucose.

Mechanism Of Interaction

Hepatic or peripheral glucose disposal, improved insulin activity

Literature Reports

A) After 3 weeks, the postprandial blood sugar was significantly reduced by 54% in 5 patients with diabetes using aqueous extracts of karela (bitter melon) but not in 5 patients using the dried powdered karela fruit in whom blood sugar was reduced by 25%. Blood sugar levels continued to gradually diminish to within normal limits over a 7-week period. Glycosylated hemoglobin was significantly reduced in 7 patients from a mean of 8.37 +/- 0.39% to 6.95 +/- 0.46% .

B) Karela (bitter melon) juice from the unripe fruit was given in 100 mL doses 30 minutes prior to a glucose tolerance test (GTT) to 18 previously unmedicated patients with newly diagnosed maturity-onset diabetes. Thirteen patients (73%) showed significant improvement at 2 and 2.5 hours after the glucose load over a previous GTT when 100 mL of water was consumed instead of the juice. The combined data for patients showed the total AUC for glucose was significantly less when karela was taken (187 cm(2)) than under control conditions (243.6 cm(2)) .

C) Nine Asian outpatients with non-insulin dependent diabetes mellitus (6 men and 3 women) were administered three separate 50-gram oral glucose tolerance tests: a standard test, a test with 50 mL karela (bitter melon) juice, and a test after 8 to 11 weeks of ingesting fried karela 0.23 kg daily. Plasma glucose concentrations decreased after karela juice administration as evidenced by a decrease in AUC, which was 5.8 +/- 3.4 mmol/L/min versus 7 +/- 2.6 mmol/L/min after the standard test at 60 to 90 minutes. Glucose AUC also decreased following intake of fried karela to 5.6 +/- 1.8 mmol/L/min at 60 to 90 minutes. Glycosylated hemoglobin significantly decreased in patients ingesting fried karela (17.9 +/- 3.1%) and in patients taking karela juice (19.2 +/- 2%) when compared to the standard test (19.6 +/- 2.2%). Insulin levels were not increased .

D) A 40 year old woman with diabetes mellitus treated with chlorpropamide continued to experience frequent glucosuria as evidenced on daily urine analysis with Clinistix(R) (glucose concentrations frequently exceeded 2 mg/dL). Ingestion of karela (bitter melon) with chlorpropamide reduced the incidence of glucosuria and the dosage of chlorpropamide was reduced. Doses of karela and chlorpropamide and the time frame for this observation were not provided . This report was disputed by another researcher, stating that karela was found to keep the indicator dye in the glucose-oxidase strips and the alkaline copper salts in a reduced state, therefore causing a false negative urine glucose. Patients with blood glucose levels of 200 mg/dL to 275 mg/dL tested negative for urine glucose after eating karela .

Pioglitazone Overview

• Pioglitazone is used with a diet and exercise program and sometimes with other medications, to treat type 2 diabetes (condition in which the body does not use insulin normally and therefore cannot control the amount of sugar in the blood). Pioglitazone is in a class of medications called thiazolidinediones. It works by increasing the body's sensitivity to insulin, a natural substance that helps control blood sugar levels. Pioglitazone is not used to treat type 1 diabetes (condition in which the body does not produce insulin and, therefore, cannot control the amount of sugar in the blood) or diabetic ketoacidosis (a serious condition that may develop if high blood sugar is not treated).

• Over time, people who have diabetes and high blood sugar can develop serious or life-threatening complications, including heart disease, stroke, kidney problems, nerve damage, and eye problems.Taking medication(s), making lifestyle changes (e.g., diet, exercise, quitting smoking), and regularly checking your blood sugar may help to manage your diabetes and improve your health. This therapy may also decrease your chances of having a heart attack, stroke, or other diabetes-related complications such as kidney failure, nerve damage (numb, cold legs or feet; decreased sexual ability in men and women), eye problems, including changes or loss of vision, or gum disease. Your doctor and other healthcare providers will talk to you about the best way to manage your diabetes.

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Definitions

Severity Categories

Contraindicated

These drugs, generally, should not be used together simultaneously due to the high risk of severe adverse effects. Combining these medications can lead to dangerous health outcomes and should be strictly avoided unless otherwise instructed by your provider.

Major

This interaction could result in very serious and potentially life-threatening consequences. If you are taking this drug combination, it is very important to be under close medical supervision to minimize severe side effects and ensure your safety. It may be necessary to change a medication or dosage to prevent harm.

Moderate

This interaction has the potential to worsen your medical condition or alter the effectiveness of your treatment. It's important that you are monitored closely and you potentially may need to make adjustments in your treatment plan or drug dosage to maintain optimal health.

Minor

While this interaction is unlikely to cause significant problems, it could intensify side effects or reduce the effectiveness of one or both medications. Monitoring for changes in symptoms and your condition is recommended, and adjustments may be made if needed to manage any increased or more pronounced side effects.

Onset

Rapid: Onset of drug interaction typically occurs within 24 hours of co-administration.

Delayed: Onset of drug interaction typically occurs more than 24 hours after co-administration.

Evidence

Level of documentation of the interaction.

Established: The interaction is documented and substantiated in peer-reviewed medical literature.

Theoretical: This interaction is not fully supported by current medical evidence or well-documented sources, but it is based on known drug mechanisms, drug effects, and other relevant information.

How To Manage The Interaction

Provides a detailed discussion on how patients and clinicians can approach the identified drug interaction as well as offers guidance on what to expect and strategies to potentially mitigate the effects of the interaction. This may include recommendations on adjusting medication dosages, altering the timing of drug administration, or closely monitoring for specific symptoms.

It's important to note that all medical situations are unique, and management approaches should be tailored to individual circumstances. Patients should always consult their healthcare provider for personalized advice and guidance on managing drug interactions effectively.

Mechanism Of Interaction

The theorized or clinically determined reason (i.e., mechanism) why the drug-drug interaction occurs.

Disclaimer: The information provided on this page is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare professional regarding your specific circumstances and medical conditions.

Where Does Our Information Come From?

Information for our drug interactions is compiled from several drug compendia, including:

• Gold Standard Drug Database
• Micromedex
• Lexicomp
• DrugBank

The prescribing information for each drug, as published on DailyMED, is also used. 

Individual drug-drug interaction detail pages contain references specific to that interaction. You can click on the reference number within brackets '[]' to see what reference was utilized.

The information posted is fact-checked by HelloPharmacist clinicians and reviewed quarterly.