RT Book, Section
A1 Smollin, Craig
A2 Papadakis, Maxine A.
A2 McPhee, Stephen J.
A2 Rabow, Michael W.
A2 McQuaid, Kenneth R.
SR Print(0)
ID 1184179597
T1 Clonidine & Other Sympatholytic Antihypertensives Overdose
T2 Current Medical Diagnosis & Treatment 2022
YR 2022
FD 2022
PB McGraw-Hill Education
PP New York, NY
SN 9781264269389
LK accessmedicine.mhmedical.com/content.aspx?aid=1184179597
RD 2023/09/24
AB Overdosage  with  these  agents  (clonidine,  guanabenz,  guanfacine,  methyldopa)  causes  bradycardia,  hypotension,  miosis,  respiratory  depression,  and  coma.  (Transient  hypertension  occasionally  occurs  after  acute  overdosage,  a  result  of  peripheral  alpha-adrenergic  effects  in  high  doses.)  Symptoms  are  usually  resolved  in  less  than  24  hours,  and  deaths  are  rare.  Similar  symptoms  may  occur  after  ingestion  of  topical  nasal  decongestants  chemically  similar  to  clonidine  (oxymetazoline,  tetrahydrozoline,  naphazoline).  Brimonidine  and  apraclonidine  are  used  as  ophthalmic  preparations  for  glaucoma.  Tizanidine  is  a  centrally  acting  muscle  relaxant  structurally  related  to  clonidine;  it  produces  similar  toxicity  in  overdose.