Drug Interactions With Quinine
Quinine may reduce the body's ability to remove digoxin, thereby increasing digoxin levels. Combining these medications may increase your risk for digoxin side effects or toxicity. If you take digoxin and need quinine treatment, your healthcare provider may need to monitor your digoxin level using a simple blood test.
There have been cases of increased neuromuscular-blocking effects, such as decreased breathing, in people taking quinine after being given a neuromuscular-blocking medication. Neuromuscular-blocking agents are normally used during surgery. If you are planning to have surgery, and are using quinine, discuss this with your healthcare provider.
Quinine may increase phenothiazine levels in the blood, increasing the risk for side effects. This interaction has only been reported in people taking other antimalarial medications. However, because of the similarities between quinine and these other medications, it may be a good idea to watch for possible phenothiazine side effects, such as extreme sedation, if you take a phenothiazine with quinine.
Quinine may decrease the level of theophylline in the blood. If you take these medications together, your healthcare provider may choose to monitor your response to theophylline, or check your theophylline blood levels to make sure you are getting enough of the medication.
The body converts tramadol into another compound, known as the M1 metabolite, using certain liver enzymes (CYP 2D6 enzymes). This M1 metabolite is responsible for much of the pain-relieving effects of tramadol. Quinine decreases the activity of the CYP 2D6 enzymes, reducing the amount of the M1 metabolite available in the body to provide pain relief. If you take tramadol with quinine, tramadol may not work as well to relieve your pain.