When fluoxetine is used in combination with lithium your doctor will carry out more frequent check-ups. • phenytoin (for epilepsy); because (Invented name)® may influence the blood levels of this drug, your doctor may need to introduce phenytoin more carefully and carry out check-ups when given with (Invented name)®. • clozapine, (used to treat certain mental disorders), tramadol (a painkiller) or triptans (for migraine); there is an increased risk of hypertension. • flecainide or encainide (for heart problems), carbamazepine (for epilepsy), tricyclic antidepressants (for example imipramine, desipramine and amitriptyline); because (Invented name)® may possibly change the blood levels of these medicines, your doctor may need to lower their dose when administered with (Invented name)®. • warfarin or other medicines used to thin the blood; (Invented name)® may alter the effect of these medicines on the blood.