Catecholamine metabolism during clonidine withdrawal
Psychopharmacology
|January 1, 1984
Summary
Abruptly stopping clonidine can cause withdrawal symptoms. This study found clonidine withdrawal in patients with alcohol amnestic disorder led to increased noradrenergic activity and elevated blood pressure, potentially causing psychopathology.
Area of Science:
- Neuroscience
- Pharmacology
- Psychiatry
Background:
- Clonidine cessation can cause withdrawal syndrome in hypertensive patients.
- Clonidine is increasingly used for neuropsychiatric conditions in normotensive individuals.
- Understanding clonidine withdrawal effects in psychiatric patients is crucial.
Purpose of the Study:
- To investigate neurochemical, cardiovascular, and behavioral changes during clonidine withdrawal in patients with alcohol amnestic disorder.
- To assess the impact of clonidine cessation on catecholamine metabolite excretion.
- To evaluate cardiovascular and behavioral responses to clonidine withdrawal.
Main Methods:
- Seven patients with alcohol amnestic disorder received clonidine (6 µg/kg/day for 3 weeks).
- Neurochemical changes were assessed via urinary catecholamine metabolite excretion.
- Cardiovascular (heart rate, blood pressure) and behavioral changes were monitored during placebo substitution.
Main Results:
- Urinary catecholamine metabolites returned to baseline 3-5 days post-clonidine, with a notable increase in normetanephrine.
- Plasma 3-methoxy-4-hydroxyphenylglycol (MHPG), heart rate, and mean arterial pressure significantly increased 72 hours after the last clonidine dose.
- Episodic memory showed enhancement, but no other significant behavioral changes were observed during withdrawal.
Conclusions:
- Clonidine withdrawal in this patient group is associated with augmented catecholamine release and central noradrenergic activation.
- These neurochemical and cardiovascular changes may contribute to psychopathology in susceptible psychiatric patients.
- Findings highlight the importance of cautious clonidine discontinuation, especially in patients with neuropsychiatric disorders.
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