Kaaja 1994.

Methods	Randomised controlled trial.
Participants	19 women randomised (1 woman entered trial in 2 successive pregnancies). Setting: Helsinki, Finland. Inclusion criteria: women with pruritus and abnormalities of liver function. Exclusion criteria: hepatitis A and B, gallbladder pathology.
Interventions	Activated charcoal (n = 10). Activated charcoal as a water suspension, 50 g 3 times a day for 8 days. vs No treatment (n = 10). Normal follow‐up of ICP with no charcoal administration. Participants maintained a daily record of pruritus: 0 = no itching; 1 = mild itching; 2 = moderate itching, does not disturb sleep; 3 = intense itching, disturbs sleep; 4 = very intense (intolerable) itching, forces participant to scratch continuously. Fasting blood samples were collected for total bile acids and LFTs at the start of the study and were repeated on day 4 and 8.
Outcomes	Maternal: status of pruritus; assays of liver function and bile acids. Fetal/neonatal: gestation at delivery, birthweight.
Notes
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Not described.
Allocation concealment (selection bias)	Unclear risk	Not described.
Blinding (performance bias and detection bias) All outcomes	High risk	Open trial.
Incomplete outcome data (attrition bias) All outcomes	Low risk	No losses to follow‐up reported.
Selective reporting (reporting bias)	High risk	Few fetal/neonatal outcomes not reported.
Other bias	Low risk	No other additional bias noted.