Pharmacologic treatments generally work by reducing the activity of excitatory neurotransmitters (such as glutamate) (e.g., pregabalin, gabapentin) or by increasing the activity of inhibitory neurotransmitters, such as norepinephrine, serotonin, and γ-aminobutyric acid or GABA (e.g., serotonin-norepinephrine reuptake inhibitors, which include duloxetine, milnacipran). After a diagnosis of depression or anxiety has been established, the next steps should be to determine whether treatment is needed or not, based on the clinical extent of severity, distress or impairment, and the patient’s preference. If pharmacologic therapy is initiated, SSRIs or SNRIs are usually the first-line therapies given their reasonable side effect profile [13]. Table 10.2 gives a comparison of the SSRIs and SNRIs available in the treatment of depression and anxiety. After initiation of medication, changes in mood can be seen within 1–2 weeks [14–16].

Drugs listed in Table 10.2 have also been found effective in the treatment of fibromyalgia-associated pain and may be considered in patients with ocular surface pain. Currently, the best-studied medications include certain SNRIs (e.g., duloxetine and milnacipran), tricyclic antidepressants (e.g., amitriptyline), and anticonvulsants (e.g., gabapentin and pregabalin) [17–19]. Interestingly, other drugs frequently used to treat pain such as nonsteroidal anti-inflammatory drugs, opioids, and corticosteroids have not been shown effective in treating fibromyalgia pain. In fact, opioids have been shown to worsen fibromyalgia-related hyperalgesia and pain in other centralized pain states [20]. It is thought that the opioid system is hyperactive in fibromyalgia patients, possibly explaining why opioids are ineffective at treating pain symptoms. As such, another promising treatment in fibromyalgia is low-dose naltrexone [21]. Naltrexone is thought to suppress microglial activity and, thereby, decrease the production of proinflammatory factors, such as cytokines, excitatory amino acids, and nitric oxide, which can cause hyperalgesia, fatigue, and other symptoms of fibromyalgia [22, 23]. In addition, trigger point injections may be beneficial in the treatment of fibromyalgia [24, 25].

The best-studied nonpharmacological therapies are education, cognitive behavioral therapy, and exercise. For the initial treatment of unipolar major depression, numerous studies have shown that the efficacy of psychotherapy and pharmacologic treatment exceeds pharmacologic treatment alone. In fibromyalgia, other treatments include chiropractic manipulation, tai chi, yoga, acupuncture, and myofascial release therapy [26, 27]. Both transcutaneous and central neurostimulatory therapies have also been used to treat pain with some success in fibromyalgia [28, 29].

These examination findings suggest that the patient has aqueous deficient dry eye (DE). The definition of dry eye provided by the 2007 international dry eye workshop (DEWS) report is “a multifactorial disease of the tears and ocular surface that results in symptoms of discomfort, visual disturbance, and tear firm instability with potential damage to the ocular surface. It is accompanied by increased osmolarity of the tear film and inflammation of the ocular surface” [30].

Given its multifactorial nature, no single test can identify all dry eye patients. A number of different diagnostic tests are used to evaluate different components of the ocular surface.