- Concomitant use of Phosphodiesterase 5 (PDE5) inhibitors, intracavernosal injections, penile implants, Selective Serotonin Reuptake Inhibitors (SSRI's) or Serotonin-Norepinephrine Reuptake Inhibitors (SSNRI's), tricyclic antidepressants (for example (e.g.) clomipramine), monoamine oxidase inhibitors, alpha blockers, 5 alpha reductase inhibitors (including propecia for hair loss), topical anaesthetics, and/or tramadol