Modafinil should not be used with certain drugs. Alcohol may cause dizziness and poor judgment. Anxiety and heart rate may increase with coffee or amphetamines. Modafinil may also interact with antidepressants, antiepileptics, and blood thinners, reducing its effectiveness or raising adverse effects. To prevent side effects, contact a doctor before using modafinil online australia with other drugs. Optimizing benefits and limiting dangers requires responsible usage.