Erectile dysfunction drugs (Cialis, Levitra, Viagra) cause amnesia.

  First it was vision loss...then hearing loss...now memory loss. All three PDE5 inhibitors...Cialis, Levitra, and Viagra...will list transient global amnesia on their labels.

  Transient global amnesia is a sudden, temporary loss of memory that usually lasts around 6 hours. People can't recall events that occurred during the episode that their memory was impaired.

  One theory is that PDE5 inhibitors inhibit phosphodiesterases in the brain...affecting levels of nitric oxide and other messengers responsible for neuronal cell to cell communication.