Methylmalonic acid (MMA) is a C-methylated derivative of malonate. Elevated levels of methylmalonic acid result from inherited defects of enzymes involved in MMA metabolism or inherited or acquired deficiencies of vitamin B12 or its downstream metabolites. MMA is also a specific diagnostic marker for the group of disorders collectively called methylmalonic acidemia.

Etiocholanone is an androstane neurosteroid. Etiocholanone potentiates GABA-A receptor currents and exerts anticolvunsant properties in rodents. Etiocholanolone demostrates pyrogenic properties.

Pregnanediol is a chief steroid metabolite of progesterone that is biologically inactive and occurs as pregnanediol glucuronate in the urine. Pregnanediol has two hydroxyl groups, at 3-alpha and 20-alpha. A test can be done to measure the amount of pregnanediol in urine. The urine test offers an indirect way to measure progesterone levels in the body. It is a standard in the colorimetric determination of urinary pregnanediol in clinical laboratories.

Androsterone, a neurosteroid, acts as a positive allosteric modulator of GABA(A) receptors, that can cross into the brain and could have effects on brain function. It was discovered, that the association of beta subunits with alpha subunits GABA(A) receptor affects the sensitivity of glycine receptors to androsterone. In spite of that, androsteron is considered as an inactive metabolite of testosterone. In addition, was studied that androsterone possessed anticonvulsant properties. Although of low potency, the androsterone was present in high abundance and was able to represent endogenous modulator of seizure susceptibility.

11-Deoxycortisol (also known as cortodoxone) is the predominant deoxycorticosteroid and is the immediate precursor of cortisol, which is formed by the enzymatic action of 11beta-hydrozylase (P450). Deficiency of this enzyme causes congenital adrenal hyperplasia, which is characterized by hypertension. 11-deoxycortisol is measured as part of the Metyrapone Test. Metyrapone blocks the formation of cortisol, resulting in increased secretion of Adrenocorticotropic hormone (ACTH) and 11-deoxycortisol in normal individuals.

Pregnanetriol is a steroid metabolite of progesterone. Elevated levels of pregnanetriol in urine indicate a disruption of adrenal steroidogenic pathways.