Chronic Cannabis Abuse, Delta-9-tetrahydrocannabinol and Thyroid Function

Abstract

Objective:

The aim of this study was to obtain rather rare information about the influence of chronic cannabis abuse on thyroid function.

Methods:

Thyroid function tests (TSH, total T₃, free T₄) of 39 chronic cannabis-dependent subjects (ICD-10) were determined at admission (for in-patient detoxification). In a subgroup, serum levels of thyroid hormones were correlated with the serum levels of delta-9-tetrahydrocannabinol (THC, N=24) and its major metabolites, THC-OH (N=16) and THC-COOH (N=24).

Results:

All of the tested patients were found to have TSH, total T₃ and free T₄ levels within the population reference range. The levels of thyroid hormones did not correlate significantly with levels of THC, THC-OH or THC-COOH in serum.

Conclusion:

These results argue against a relevant influence of chronic cannabis intake on thyroid function in humans.

Key words

THC - TSH - thyroid hormones - cannabis-dependence

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