Several herbs can affect your brain’s neurotransmitters, which are brain chemicals. An imbalance in these chemicals plays a direct role in depression because they are linked to mood, according to the National Institute of Mental Health. Other neurotransmitters affect your ability to make memories and think. Herbs can boost mood and may even help conditions like early Alzheimer’s. However, before you take any herbs to treat chemical imbalances, it’s important to consult a doctor -- especially if you take medications to treat your condition.
St. John's Wort
St. John's wort has been used for centuries to treat depression and is a popular treatment for this ailment in Europe, according to the National Center for Complementary and Alternative Medicine. It’s likely most helpful if you have moderate or mild depression. It may even work as well as some antidepressant medications without the side effect of libido loss, according to the University of Maryland Medical Center. Though available research has not pinpointed the exact mechanism by which St. John’s wort works, according to UMMC, one theory states the herb acts like an SSRI, or selective serotonin reuptake inhibitor. This makes more of the chemicals dopamine, serotonin and norepinephrine available to your brain. The National Institutes of Health gives this herb an “A” rating for treating mild to moderate depression, meaning there is strong scientific evidence to support this use.
Ginkgo biloba may normalize brain chemicals that are altered by stress, reports a study published in the October 2003 issue of "European Neuropsychopharmacology." Ginkgo restored elevated levels of stress-induced brain chemicals norepinephrine and dopamine to near-normal levels, Shah’s study found. Since stress and mental problems associated with it have increased tremendously in the modern-day world, ginkgo may be a valuable natural alternative for treating it, though more study is needed, Shah advises. Because ginkgo also raises serotonin levels, people who take SSRIs risk serotonin syndrome, a potentially fatal condition in which a person has too much serotonin in his body, warn the experts at UMMC. Ginkgo also can enhance both good and bad effects of MAOIs, or monoamine oxidase inhibitor antidepressants, like phenelzine.
MedlinePlus.com states ginkgo is effective for treatment of early-stage Alzheimer's disease and dementia.
Lavender has a long history of use in treating depression, anxiety and insomnia, according to UMMC. Though the exact mechanism hasn’t been discovered, the lead theory is that when you inhale its scent, smell receptors in your nose send chemical messages along your nerve pathways to your brain's limbic system, which affects mood, reports the American Cancer Society. Since lavender promotes relaxation, you need to consult a doctor before using it with central nervous system depressants because it may make their effects stronger, advise the experts at UMMC. Such drugs include narcotics like oxycodone and morphine as well as sedative and anti-anxiety drugs like lorazepam, diazepam or alprazolam. More research is needed to recommend lavender aromatherapy as a treatment for chemical imbalance.