IV Thrombolysis: Contraindications & Special Conditions
This article summarizes absolute and relative contraindications to IV thrombolysis, as well as special clinical scenarios where treatment may be considered.
Contraindications to IV Thrombolysis
| Contraindication | Timing / Context | Guideline Statement | COR / LOE |
|---|---|---|---|
| Mild non-disabling stroke 2026 | NIHSS 0–5 with non-disabling symptoms | IVT is not recommended; no superiority vs DAPT (PRISMS trial) | Class 3: No Benefit (B-R) |
| Extensive hypoattenuation on CT | Frank hypodensity / subacute stroke | Not recommended; indicates irreversible injury | Class 3 |
| Acute intracranial hemorrhage | On CT | Contraindicated | Class 3: Harm |
| Ischemic stroke within prior 3 months | History | Potentially harmful | Class 3 |
| Severe head trauma | Within 3 months | Contraindicated | Class 3: Harm |
| Intracranial or intraspinal surgery | Within 3 months | Potentially harmful | Class 3 |
| History of intracranial hemorrhage | Any time | Potentially harmful | Class 3 |
| Clinical suspicion of SAH | Presentation | Contraindicated | Class 3: Harm |
| GI malignancy | History | Potentially harmful | Class 3 |
| GI bleeding | Within 21 days | Potentially harmful | Class 3 |
| Coagulopathy (platelets <100k, INR >1.7, aPTT >40s) | At baseline | Contraindicated | Class 3: Harm |
| LMWH use (therapeutic dose) | Within 24 hours | Contraindicated | Class 3: Harm |
| Direct thrombin or factor Xa inhibitors | Within 48h | Not recommended unless cleared by lab or time | Class 3 |
| Concomitant IV abciximab | Within 90 minutes | Contraindicated | Class 3: Harm |
| Infective endocarditis | Clinical suspicion | Contraindicated | Class 3: Harm |
| Aortic arch dissection | Known or suspected | Contraindicated | Class 3: Harm |
| Intra-axial intracranial tumor | Known | Potentially harmful | Class 3 |
| TNK 0.4 mg/kg dose 2026 | Any patient | Higher TNK dose is not recommended — no benefit, potential harm | Class 3: No Benefit (A) |
Special Clinical Conditions for IV Thrombolysis
| Condition | Timing / Context | Guideline Summary | COR / LOE |
|---|---|---|---|
| Cerebral microbleeds — unknown burden 2026 | MRI not available | Do NOT delay IVT to obtain MRI to exclude CMBs | Class 1 (B-NR) |
| Cerebral microbleeds — 1–10 CMBs 2026 | Known from prior MRI | IVT is reasonable to achieve better functional outcomes | Class 2a (B-NR) |
| Cerebral microbleeds — >10 CMBs 2026 | Known from prior MRI | Usefulness uncertain; may increase sICH risk. Individualize. | Class 2b (B-NR) |
| Single or dual antiplatelet therapy 2026 | Prior to stroke | IVT is recommended despite increased sICH risk vs no antiplatelet | Class 1 (B-NR) |
| Coagulation testing 2026 | No reason to suspect abnormality | Reasonable NOT to delay IVT for lab results | Class 2a (B-NR) |
| Age >80 | 3–4.5h window | IVT is safe and effective, similar to younger patients | Class 1 |
| Diabetes + prior stroke | 3–4.5h window | IVT may be reasonable; outcomes similar to 0–3h | Class 2a |
| Severe stroke (NIHSS >25) | 3–4.5h window | Benefit uncertain; decision individualized | Class 2b |
| Mild but disabling stroke | Within 4.5h | Reasonable to treat if deficits are disabling | Class 2a |
| Wake-up or unknown onset | DWI-FLAIR mismatch | IVT can be beneficial within 4.5h of symptom recognition | Class 2a (B-R) |
| Preexisting disability | Any time | May be reasonable; consider goals of care | Class 2b |
| Early improvement | Any time | Reasonable if residual deficits remain disabling | Class 2a |
| Seizure at onset | Any time | Reasonable if deficit attributed to stroke, not postictal | Class 2a |
| Early ischemic changes (mild-moderate) | On NCCT | IVT recommended; does not modify treatment effect | Class 1 (A) |
| Hypo/hyperglycemia | Initially abnormal | Correct glucose; IVT if deficits persist | Class 1 (C-LD) |
| Warfarin use | INR ≤1.7 | Reasonable to treat | Class 2a |
| Recent lumbar puncture | Within 7 days | May be considered | Class 2b |
| Recent arterial puncture | Non-compressible site, <7 days | Uncertain benefit; case-by-case | Class 2b |
| Recent major trauma (non-head) | <14 days | Reasonable; weigh stroke risk vs. bleeding | Class 2b |
| Recent major surgery | <14 days | May be considered if benefit outweighs risk | Class 2b |
| Menstruation | Ongoing or recent | Reasonable in most cases | Class 2a |
| Extracranial cervical dissection | <4.5h | Probably safe and reasonable | Class 2a |
| Unruptured aneurysm (<10mm) | Known | Reasonable to treat | Class 2a |
| Cardiac thrombus / MI history | Recent MI | May be considered; STEMI location influences risk | Class 2b |
| Pregnancy | Any time | Reasonable if benefit outweighs bleeding risk | Class 2a |
| Stroke mimics | Presentation | Reasonable to treat; sICH risk is low | Class 2a |
| Pediatric patients (28 days–18 years) 2026 | Within 4.5h, disabling deficits | IVT with alteplase may be considered; safe but efficacy uncertain | Class 2b (C-LD) |
🔹 Clinical Pearl: Shared Decision-Making
- When patients cannot provide consent (e.g., aphasia) and a legally authorized representative is not immediately available, it is justified to proceed with IVT in an otherwise eligible adult with disabling deficits (Class 1, C-EO) 2026
- Discuss potential risks and benefits with competent patients and/or representatives when feasible
References
- Prabhakaran S, et al. 2026 Guideline for the Early Management of Patients With Acute Ischemic Stroke. Stroke. 2026;57:e00–e00.
- Powers WJ, et al. 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke. Stroke. 2019;50:e344–e418.
- Demaerschalk BM, et al. Scientific Rationale for the Inclusion and Exclusion Criteria for Intravenous Alteplase in Acute Ischemic Stroke. Stroke. 2016;47:581–641.