Subjects who received L-glutamine oral powder also had fewer occurrences of acute chest syndrome (a life-threatening complication of sickle cell disease) compared with patients who received a placebo (8.6 percent vs. 23.1 percent).Common side effects of L-glutamine oral powder include constipation, nausea, headache, abdominal pain, cough, pain in the extremities, back pain and chest pain.L-glutamine oral powder received orphan drug designation. The FDA granted the approval of Endari to Emmaus Medical Inc.

Medical food
Glutamine is marketed as medical food and is prescribed when a medical professional believes a person in their care needs supplementary glutamine due to metabolic demands beyond what can be met by endogenous synthesis or diet. Safety
Glutamine is safe in adults and in preterm infants. Although glutamine is metabolized to glutamate and ammonia, both of which have neurological effects, their concentrations are not increased much, and no adverse neurological effects were detected. The observed safe level for supplemental L-glutamine in normal healthy adults is 14 g/day.Adverse effects of glutamine have been prescribed for people receiving home parenteral nutrition and those with liver-function abnormalities. Although glutamine has no effect on the proliferation of tumor cells, it is still possible that glutamine supplementation may be detrimental in some cancer types.Ceasing glutamine supplementation in people adapted to very high consumption may initiate a withdrawal effect, raising the risk of health problems such as infections or impaired integrity of the intestine. Structure
Glutamine can exist in either of two enantiomeric forms, L-glutamine and D-glutamine. The L-form is found in nature.
Many textile mills and fiber producing factories located in LMICs have high rates of chronic respiratory disease caused by byssinosis.The term "brown lung" is a misnomer, as the lungs of affected individuals are not brown. Byssinosis is also referred to as cotton workers lung, mill fever, brown lung disease, and Monday fever. History
In 1971, the Occupational Safety and Health Administration (OSHA) set a permissible exposure limit (PEL) of  1-mg/m3 (total dust) for cotton dust in work places. Later in the 1978 OSHA developed the Cotton Dust Standard which aimed to prevent occupational respiratory disease, such as byssinosis, through medical monitoring of employees. The PEL of cotton dust was set to 0.2 mg/m3 of airborne dust. This was considered the lowest level that could be measured by the vertical elutriator cotton dust sampler.OSHA regulators hoped that the Cotton Dust Standard Act would help decrease the impact of dust exposure of employees and reduce occupational respiratory diseases. However, a NISOH sponsored committee remained apprehensive about this standard as an earlier study conducted by NIOSH found that byssinosis diagnoses were brought on by cotton dust levels as low as 0.1 mg/m3 meaning that there is still a risk for the development of byssinosis for cotton dust exposure under the PEL. Today, NIOSH has set a recommended exposure limit (REL) of cotton dust to less than 0.2 mg/m3 for up to a 10-hour workday. Symptoms
Symptoms of byssinosis can include:
Cough with sputum
Dyspnea
Breathing difficulties
Chest tightness
Wheezing
CoughPatients can develop these symptoms after a few hours of exposure at minimum.