Have used 'Behave Paste' for at least the last 6 yrs. I follow the instructions. All years my horses have hardly worried with fireworks bangs, hissing, light explosions etc. I also turn radio on loudly plus all yard lights to lesson the impact of the fireworks; and feed hay to divert attention.
Appears to work for my purpose: helps calm my horses. No actual 'drug' in the product.
Typical horses resent pasting so I feed lucerne hay afterwards. It stains amber, but washes off OK.