Many patients show aggressiveness and self-injurious behaviours, and sleep disturbances are common. Specific behaviours resembling those of people with autism are often present as well as hyperactivity, which provides genetic and biological insights into autism spectrum disorders. The autistic behaviours most characteristic of SLOS patients are opisthokinesis (an upper body movement), stretching of the upper body, and hand flicking. Autism is typically diagnosed separately from SLOS using the DSM-V, and approximately 50–75% of SLOS patients meet the criteria for autism.Other behaviours associated with SLOS can be linked directly to physical abnormalities. For example, infants often show feeding problems or feeding intolerance, and patients may require increased caloric intake due to accelerated metabolism. Recurrent infections, including ear infections and pneumonia, are also common. Biochemical phenotype
Given that SLOS is caused by a mutation in an enzyme involved in cholesterol synthesis, the resulting biochemical characteristics may be predictable. Most patients have lowered plasma cholesterol levels (hypocholesterolemia). However, approximately 10% may show normal cholesterol levels,  and decreased concentrations of cholesterol are not solely indicative of SLOS. Increased levels of cholesterol precursors are also common in SLOS. In particular, elevated levels of 7-dehydrocholesterol are fairly specific to SLOS. Genetics
DHCR7
The gene encoding DHCR7 (labeled as DHCR7) was cloned in 1998, and has been mapped to chromosome 11q12-13. It is 14100 base pairs of DNA in length, and contains nine exons, the corresponding mRNA is 2786 base pairs in length (the remaining DNA sequence is intronic).
Hydrocodone/ibuprofen (INNs), sold under the brand name Vicoprofen, is a fixed-dose combination analgesic medication used in short-term therapy to relieve severe pain. Vicoprofen combines the analgesic and antitussive properties of hydrocodone with the analgesic, anti-inflammatory, and antipyretic properties of ibuprofen. In contrast to hydrocodone/acetaminophen combination analgesics such as Vicodin, this hydrocodone/ibuprofen avoids some of the liver toxicity which may occur from acetaminophen, but still presents significant dangers in hydrocodone overdose, namely respiratory depression. Vicoprofen is supplied in a fixed dose combination tablet which contains hydrocodone bitartrate, USP 7.5 mg with ibuprofen, USP 200 mg.  Additional strengths of generic Vicoprofen are now available, in combinations of 5 mg/200 mg and 10 mg/200 mg respectively. Medical uses
Hydrocodone/ibuprofen has a labeled indication for "short-term (generally <10 days) management of acute pain severe enough to require an opioid analgesic and for which alternative treatments are inadequate". Pregnancy
Opioids such as hydrocodone cross the placenta, and can therefore affect the fetus. Studies have shown a possible association between opioids and adverse outcomes such as birth defects, poor fetal growth, stillbirth, and preterm delivery. Prolonged use of opioids by a pregnant mother can also lead to neonatal withdrawal syndrome. NSAIDs such as ibuprofen should generally be avoided in pregnancy, as there are conflicting reports of birth defects after in utero exposure. However, it is accepted that NSAIDs prevent closure of the fetal ductus arteriosus, which happens during the later stages of pregnancy. Because of this, ibuprofen should be avoided after 30 weeks gestation.