Huoxue Zhitong Plaster (Blood-activating and Pain-relieving plaster) is a traditional Chinese medicine (TCM) patch used to treat muscle pain, joint pain, strains, and arthritis by improving circulation and reducing swelling. These herbal patches are typically applied directly to the affected area for pain relief. 
 
Key Details and Benefits:
Uses: Relieves pain from sports injuries, stiff neck, backache, and arthritis.
Mechanism: Promotes blood circulation to remove blood stasis (huoxue) and relieves pain (zhitong).
Application: Easy to apply, sometimes cut to size, and can often be used for several hours.
Ingredients: Often contains a blend of herbs such as notoginseng, safflower, and frankincense. 
 
Safety and Usage Precautions:
Skin Irritation: Some users may experience rashes, itching, or, in rare cases, burns.
Contraindications: Do not use on broken skin, open wounds, or if allergic to the ingredients.
Duration: Consult a doctor if symptoms persist for more than 7 days.