Anti-depressants are one of the most commonly prescribed classes of medication in the world. They are primarily used to treat depression, but can be used to treat other psychiatric disorders and although they are not specifically intended to treat pain, they have also become a mainstay in the treatment of chronic pain.
It is believed that anti-depressants increase the neurotransmitters in the brain and spinal cord that decrease pain signals. Pain-relieving effects are not immediate and may take several weeks to provide maximum benefit. Many people report moderate pain relief from antidepressants and anti-seizure medications may accompany anti-depressants if the pain relief is incomplete.
There are several classes of antidepressants believed to decrease chronic pain, this includes: amitriptyline, desipramine, imipramine and nortriptyline. The pain involved in the following medical conditions can be responsive to these types of anti-depressants:
- Diabetic peripheral neuropathic pain
- Post herpetic neuralgia
- Nerve pain from other causes
- Facial pain
- Tension headache
- Low back pain
- Pelvic pain
Antidepressants have common adverse effects, which can be minimized by timely diagnosis and management. Some of the most common when using antidepressants include:
- Weight gain
- Sexual dysfunction
- Sleep disturbances
- Agitation or worsening of anxiety
- Suicidal thoughts
While more research needs to be conducted to better understand how antidepressants reduce pain, they are a widely accepted part of a multidisciplinary treatment approach.