The investigators want treat Vulnerable plaque of carotid artery with a herbal and insects Chinese medicine. Designing a RCT trial to prove the effect and safety.

Vulnerable plaque of carotid artery is the important intervention target for primary prevention and secondary prevention of cerebral arterial thrombosis, but there are no effective, safe and prevalent treatment measures against it. The development that traditional Chinese medicine has achieved in treating plaque of carotid artery shows that great accomplishment could be made within this area. Academia should engage in clinical research on regulated treatment methods in traditional Chinese medicine with long-term intervention and high patient compliance, providing strong evidence for evidence-based medicine and guidance to clinical practice.

Inclusion Criteria:

1. Meet the diagnostic criteria of carotid artery atherosclerosis;
2. Ultrasound of carotid artery atherosclerosis plaque specifies it as unstable plaque (including malacoplakia and mixed plaque);

Exclusion Criteria:

1. mRS Rating higher than or equal to 3 before joining the trail group;
2. Carotid artery stenosis is higher than or equal to 50%;
3. Confirmed as or suspected to be vasculitis;
4. With infection, tumor or insufficient heart, liver and kidney functions (renal function higher than twice of upper limit in normal limit, HYHA heart function grading higher than or equal to level 2 );
5. With acute myocardial infarction and unstable angina pectoris;
6. With acute cerebral arterial thrombosis;
7. lesion: Severe stenosis or occlusion of distal intracranial vessels;
8. Pregnant women or lactating mothers;
9. With known history of allergy to the drugs of the trial.