STUDIES ON LITHIUM METABOLISM IN
PSYCHIATRIC
DISORDER.
By
Madhav G.
Kalekar.
A B S T R A C T
Lithium is the third lightest element after hydrogen
and helium in the periodic table and is used in psychiatric
illness for the treatment of manic Depressive psychosis
patients. It is potentially toxic drug and therefore require
an oral dose adjustment and blood level maintainance during
therapy under careful laboratory Supervision. Lithium is
effective in the control of psychiatric illness of affective
disorders and is require long term therapy for better
response and further follow up study. Lithium stabilizes the
mood of the patient by altering the electrolyte metabolism.
Though the lithium is effective in the treatment, it may
develops the severs toxic side effect and abnormalities of
thyroid function and kidney function if the does was not
maintained properly with regular interval of time, which
have been described in chapter I
The second chapter of the thesis
deals with an
administration of a single dose of lithium oral intake
its absorption period^ blood level maintainance & excretion
rates carried out on the patients receiving lithium treatment
for the first time. It was observed that maximum pick levels
of lithium concentrations were obtained after four hours of
initial intake after which it was slowly excreted in urine
within twenty four hours and total 9 2 % of intial intake of
lithium concentration recovered in twenty four hours urine
sample. This finding may be helpful for the patients and
doctors in maintaining serum lithium level within therapeutic
range for effective treatment and to avoid toxicity. It has
been shown that lower levels of lithium are not effective
while increased levels above 1.5mEg/L can cause lithium
toxicity and toxic side affect of fine hand tremor excessive
thirst, polyuria etc. Therefore effective therapeutic
of serum lithium should b e within
range
0.5 to 1.5me^/L fd>r the
ma i nt a i na nc e-ifre a tme nt.
In the IV,3£ and VI chapters effect of Lithium on the
body functions was carried out with the help of kidney functioi
test, thyroid function test and enzymes studies before the
commencement of the therapy and then during the lithium
therapy at intervals of eight days, fifteen days and one
month period. It was observed that therapy did not causes
any abnormalities in the kidney function, thyroid
function
and enzymes studies even after one month of the therapy
and patients improves clinically better after one month.
Lithium treatment can be continued after one month
for
the better follow u p of the patients.
Since lithium is included in the category of an
electrolyte, its effect on the status of the body electrolyte
concentration was studied
in chapter IV. Thus
concentration
of serum sodium potassium, magnesium and calcium were
measured before and after the initiation of lithium treatment
after a period of 8 days, 15 days and one months. It was
observed that serum potassium and sodium levels were normal
before treatment while serum calcium and magnesium levels
were decresed. After lithium treatment serum sodium levels
were decreased whereas serum calcium and magnesium levels
were elevated after one month of treatment. This finding
suggest that lithium may be influencing to currect the
electrolyte balance necessary for brain function.
In addition to these measurement we also determined the
RBC Na and K levels before and after lithium treatment.
It was found that before lithium treatment RBC Na levels were
decreased and RBC K were normalised but after lithium treatment
RBC Na increased and normalised whereas RBC K levels were
not affected. This finding indicates that decreased levels of
RBC Na before therapy may be contributing to manic state of
the patient which are currected after therapy by normalizing
the RBC Na levels without affecting the RBC K levels. Which
have been described in chapter VII.
Artificial lithium transport through RBC membrane were
carried out using synthetic ionophores which have been decribed
in last chapter (VIII)
Manic patients have shown enhanced
levels of RBC lithium level than the control group.
With using
the synthetic ionophore the normal subjects have shown enhanced
levels of RBC lithium level than manic patients. In the
presence of a synthetic ionophore the lithium content of RBC's
in normal subjects was found to1, be increased while no change was
observed in manic patients. The transport rate of lithium
across RBC membrane in the both groups is similar.