What do systematic reviews say?

C1 esterase inhibitor vs placebo or active control

C1 esterase inhibitor showed no clear difference in adverse events (during compared with placebo or active control (moderate certainty).

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  RR 1.03 [0.84, 1.27]
  1 study · 44 participants
  Moderate

C1 esterase inhibitor vs placebo or active control

It is very uncertain whether C1 esterase inhibitor changes serious adverse events (during compared with placebo or active control (very low certainty).

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  RR 0.34 [0.01, 8.14]
  1 study · 44 participants
  Very low

Nanofiltered C1 esterase inhibitor vs placebo or active control

The review found no eligible studies for this question.

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Plasma‐derived C1 esterase inhibitor vs placebo or active control

Plasma‐derived C1 esterase inhibitor showed no clear difference in adverse events(during compared with placebo or active control (low certainty).

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  RR 1.05 [0.78, 1.42]
  1 study · 71 participants
  Low

Recombinant human C1 esterase inhibitor vs placebo or active control

Recombinant human C1 esterase inhibitor showed no clear difference in adverse events(during compared with placebo or active control (low certainty).

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  RR 1.39 [0.71, 2.7]
  1 study · 29 participants
  Low

Nanofiltered C1 esterase inhibitor vs placebo or active control

The review found no eligible studies for this question.

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  no estimate extracted
  Studies not reported
  No studies found

Plasma‐derived C1 esterase inhibitor vs placebo or active control

It is very uncertain whether plasma‐derived C1 esterase inhibitor changes serious adverse events (during compared with placebo or active control (very low certainty).

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  RR 0.54 [0.09, 3.1]
  1 study · 71 participants
  Very low

Recombinant human C1 esterase inhibitor vs placebo or active control

It is very uncertain whether recombinant human C1 esterase inhibitor changes serious adverse events (during compared with placebo or active control (very low certainty).

• Interventions for the long‐term prevention of hereditary angioedema attacks 2022 · Cochrane Headline outcomes only
  RR 1.5 [0.06, 34.66]
  1 study · 29 participants
  Very low

Phosphodiesterase inhibitors vs placebo

• Vasodilators for primary Raynaud's phenomenon 2021 · Cochrane Headline outcomes only
  no estimate extracted
  3 studies · 138 participants
  GRADE not reported