Are there any medicines cumin should not be taken with?

Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.
Cumin might decrease blood sugar. Diabetes medications are also used to lower blood sugar. Taking cumin along with diabetes medications might cause your blood sugar to go too low. Monitor your blood sugar closely. The dose of your diabetes medication might need to be changed.

Some medications used for diabetes include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), tolbutamide (Orinase), and others.

Medications that slow blood clotting (Anticoagulant / Antiplatelet drugs)
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.
Cumin might slow blood clotting. Taking cumin along with medications that also slow blood clotting might increase the chances of bruising and bleeding.

Some medications that slow blood clotting include aspirin, clopidogrel (Plavix), dalteparin (Fragmin), enoxaparin (Lovenox), heparin, ticlopidine (Ticlid), warfarin (Coumadin), and others.

Rifampin
Interaction Rating: Moderate Be cautious with this combination.
Talk with your health provider.
Cumin might increase how much rifampin the body absorbs. Taking cumin along with rifampin might increase the effects and side effects of rifampin.

Dosing considerations for Cumin.
The appropriate dose of cumin depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for cumin. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other health care professional before using.

Source: RxList.com