SIADH

Question 1

What are symptoms of SIADH?

Answer 1

Nausea and vomiting
Confusion and lethargy
Irritability
Muscular spasm and cramp
Seizures

Question 2

What are the criteria for diagnosis of SIADH?

Answer 2

Decreased serum osmolality
Increased urine osmolality
Euvolaemia
Increased urine sodium >20
No other cause for hyponatraemia

Question 3

What are the most common psych drug causes of SIADH?

Answer 3

Carbamazepine
SSRIs
TCAs
MAOis
Venlafaxine
NSAIDs
Antipsychotics
PPIs
Nicotine
Amiodarone
Cyclophosphamide
Chlorpropamide
Oxcarbazepine

Question 4

How long does SIADH take to develop after starting a new drug?

Answer 4

few weeks

Question 5

What is the treatment of SIADH?

Answer 5

Fluid restriction
Demeclocycline

Question 6

What drug when used in conjunction with SSRIs increases the risk of SIADH?

Answer 6

ACE inhibitors

Question 7

What are RFs for developing hyponatraemia with psychotropic medication ?

Answer 7

Increasing age, female
Low body weight
History of hyponatraemia
Baseline low levels
Summer
Early onset psychiatric illness, longer duration of psych disorder, prolonged admission
Comorbidities - DM, HTN, COPD, HF, hypothyroidism, head injury, stroke, cirrhosis, malignancy
Meds - diuretics, anti-HTNs, antidepressants, CYP450 inhibitors
During initial phase of treatment