He theorized that the reduction in available natural light during winter was the cause. Rosenthal and his colleagues then documented the phenomenon of SAD in a placebo-controlled study utilizing light therapy. A paper based on this research was published in 1984. Although Rosenthals ideas were initially greeted with skepticism, SAD has become well recognized, and his 1993 book, Winter Blues has become the standard introduction to the subject.Research on SAD in the United States began in 1979, when Herb Kern, a research engineer, had also noticed that he felt depressed during the winter months. Kern suspected that scarcer light in winter was the cause, and discussed the idea with scientists at the NIMH who were working on bodily rhythms. They were intrigued, and responded by devising a lightbox to treat Kerns depression. Kern felt much better within a few days of treatments, as did other patients treated in the same way. Signs and symptoms
SAD is a type of major depressive disorder, and those with the condition may exhibit any of the associated symptoms, such as feelings of hopelessness and worthlessness, thoughts of suicide, loss of interest in activities, withdrawal from social interaction, sleep and appetite problems, difficulty with concentrating and making decisions, decreased libido, a lack of energy, or agitation. Symptoms of winter SAD often include falling asleep earlier or in less than 5 minutes in the evening, oversleeping or difficulty waking up in the morning, nausea, and a tendency to overeat, often with a craving for carbohydrates, which leads to weight gain.
Specific populations
Pregnancy
Ceftriaxone is pregnancy category B. It has not been observed to cause birth defects in animal studies, but a lack of well-controlled studies done in pregnant women exists. Breastfeeding
Low concentrations of ceftriaxone are excreted in breast milk that are "not expected to cause adverse effects in breastfed infants." The manufacturer recommends that caution be exercised when administering ceftriaxone to women who breastfeed. Newborns
Hyperbilirubinemic neonates are contraindicated for the use of ceftriaxone. It can compete with bilirubin and displace it from binding to albumin, increasing the risk of bilirubin encephalopathy. Elderly
According to the package insert, clinical studies did not 
show differences in efficacy and safety of ceftriaxone in geriatrics compared to younger patients but "greater sensitivity of some older individuals cannot be ruled out." Adverse effects
Although generally well tolerated, the most common adverse reactions associated with ceftriaxone are changes in white blood cell counts, local reactions at site of administration, rash, and diarrhea.Incidence of adverse effects greater than 1%:

Eosinophilia (6%)
Thrombocytosis (5.1%)
Elevations in liver enzymes (3.1–3.3%)
Diarrhea (2.7%)
Leukopenia (2.1%)
Elevation in BUN (1.2%)
Local reactions: pain, tenderness, irritation (1%)
Rash (1.7%)Some less frequently reported adverse events (incidence < 1%) include phlebitis, itchiness, fever, chills, nausea, vomiting, elevations of bilirubin, elevations in creatinine, headache and dizziness.Ceftriaxone may precipitate in bile, causing biliary sludge, biliary pseudolithiasis, and gallstones, especially in children. Hypoprothrombinaemia and bleeding are specific side effects. Haemolysis is reported. It has also been reported to cause post kidney failure in children. Like other antibiotics, ceftriaxone use can result in Clostridium difficile-associated diarrhea ranging from mild diarrhea to fatal colitis.