Is lysergic acid diethylamide (LSD) metabolized in the body?
Short answer
LSD appears to be enzymatically broken down in the liver.

Background
First off, hormones do not break down anything; enzymes are the work horses that mediate metabolism. 

According to a review paper (Passie et al., 2008), humans metabolize LSD into structurally similar metabolites (Fig. 1) by NADH-dependent microsomal liver enzymes to the inactive 2-oxy-LSD and 2-oxo-3-hydroxy LSD. LAE is formed through enzymatic N-dealkylation of the diethylamide
radical at side chain position 8. Di-hydroxy-LSD and nor-LSD are also metabolites, as well as 2-oxo-LSD, 13- and 14-hydroxy-LSD as glucoronides, lysergic acid ethyl-2-hydroxyethylamide (LEO), and trioxylated LSD.

Note that the monoamine oxidase (MAO) system is unlikely to break down LSD. MAO are enzymes that catalyze the oxidation of monoamines. Monoamine neurotransmitters contain one amino group that is connected to an aromatic ring by a two-carbon chain (such as -CH2-CH2-). This structure is not present in LSD (fig. 1). A cursory Google Scholar search did not yield any relevant hits ('LSD' + 'monoamine oxidase'), loosely indicating that MAO is unlikely to be involved in LSD metabolism. However, as I suspect some self-help here - I am unsure about MAOI and LSD interactions, and I highly discourage any toying around with MAO inhibitors and any drug in general. For example, 5-HT is a typical example of an MAO substrate and LSD impinges on 5-HT2A receptors. Hence, interactions in pharmacodynamics with combined LSD and MAOI intake are likely to occur.


Fig. 1. LSD metabolites. source: Passie et al. (2008)

Reference
- Passie et al., CNS Neuroscience &amp; Therapeutics (2008); 14: 295–314