It is not unusual for a missed dose of Cymbalta to trigger headaches or other feelings of anxiety or general malaise, especially if the drug is taken once a day. The headache or other symptoms ought to improve in a few days Best of luck to you.
Omgoodness! I was recently put on tompomax for tension/migraine headaches. I have suffered from headaches typically about once or twice a week for almost all of my life but occassionally will have the migraine that paralyzes me to the bed for a day or two. I have been taken cymbalta for exactly one month yesterday. I take my pill before bed time and didnt realize i had forgotten to refill my prescription. So I woke up with a headache and it only worsened throughout the day that by lunch i was in the bed crying. I had to get my mom to pick up my prescription for me because I could not drive. I have not had a headache like this is I dont know how long. So I definitely think missing a dose could cause a headache but I would like to know why!?
Nobody knows for sure, but cymbalta increases the duration of serotonin and norepinepherine in nerve synapses, suppressing acetylcholine (a pain and muscle stimulating messenger), and increasing the release of dopamine (a "well" feeling and relaxing neurotransmitter). Missing a dose of cymbalta can tip the balance back to increased acetylcholine release, resulting in restlessness, increased pain, and increased blood pressure.
It seems to have been it. Once she resumed her meds at her normal time, her migraine and anxiety went away.