Diuretic effect on amantadine levels, hallucinations, falls

[aspergerian]

Taking Dyazide (hydrochlorothiazide and triamterene) while taking

amantadine reduced renal clearance of amantadine and induced adverse

effects including hallucinations (1, cited in 2).

Some medications increase orthostatic hypotension and are associated

with a higher rate of falling (3).

1. Amantadine-dyazide

interaction.

Wilson TW, Rajput AH.

Can

Med Assoc J. 1983 Nov 1;129(9):974-5.

ncbi.nlm.nih.gov/pmc/articl...

To document an interaction between amantadine hydrochloride and

Dyazide that had apparently produced amantadine toxicity, a patient

was given amantadine alone for 1 week, followed by amantadine plus

Dyazide for another week, under controlled conditions. A diuretic

effect was observed after Dyazide was added to the regimen, but the

urine amantadine excretion fell, and the drug's plasma concentration

increased. It was concluded that one or both of the components of

Dyazide (hydrochlorothiazide and triamterene) reduce the clearance

of amantadine and can produce higher plasma concentrations and toxic

effects.

2. Parkinson's

disease between internal medicine and neurology.

Csoti I, Jost WH, Reichmann H.

J Neural Transm (Vienna). 2016

Jan;123(1):3-17.

ncbi.nlm.nih.gov/pmc/articl...

3. High

prevalence of orthostatic hypotension and its correlation with

potentially causative medications among elderly veterans.

Poon IO, Braun U.

J Clin Pharm Ther. 2005 Apr;30(2):173-8.

ncbi.nlm.nih.gov/pubmed/158...

BACKGROUND: Orthostatic hypotension (OH) is defined as a reduction

of systolic blood pressure of at least 20 mmHg, or diastolic blood

pressure of at least 10 mmHg from a sitting to a standing

position. It is a common physical finding among older adults and

associated with significant morbidity and mortality. Use of

medications that have the potential to induce OH, particularly

concomitant use of several of such medications, is a major factor

for the development of OH....

RESULTS: A total of 505 individual patients attended the clinic

during the study period, and 342 patients fit the inclusion

criteria. About 189 of these patients (55%) had OH. Among patients

with OH, 61 patients (33%) were symptomatic, including 52 patients

who had falls. The prevalence of OH in patients receiving zero,

one, two, and three or more potentially causative medications was

35, 58, 60 and 65% respectively. Receiving hydrochlorothiazide was

associated with the highest prevalence of OH (65%), followed by

receiving lisinopril (60%), trazodone (58%), furosemide (56%) and

terazosin (54%).

[Hikoi]

Last article - And have Parkinsons can cause orthostatic hypotension. The drugs can make it worse.

Second article very interesting thanks.