The forehead and the frown line are normally the muscles injected for tension headaches. To see what the forehead looks like after treatment, click here to see a video: https://cityskin.com.au/anti-wrinkle/migraine-and-tension-headache-treatment/
Anti-wrinkle injections take 1-5 days to start working, and continue to work for 2 weeks. This is when the drug reaches its peak effect. Generally, patients often start to feel relief of the tension headache when the muscles start relaxing, a few days after treatment. The drug life of anti-wrinkle injections is up to 3-4 months, depending on the dose injected. Most patients will ‘know’ when it is starting to wear off because their headaches start to return.