What the label lists and what reports show
Alteplase side effects
Alteplase's FDA label lists its adverse reactions in its own words. FAERS holds 14,927 reports naming it through July 30, 2026; the reaction reported most often, leaving out the conditions it is used for, product-use terms and outcomes, is gingival bleeding (1,029 reports).
- No generic listed
- A presentation discontinued
Check it at the source: the alteplase FDA label on DailyMed (effective January 20, 2026, Genentech, Inc.); the FDA FAERS public dashboard.
What does the label list?
From the label: adverse reactionsThe following adverse reactions are discussed in greater detail in the other sections of the label: Bleeding [see Contraindications (4), Warnings and Precautions (5.1) ] Hypersensitivity [see Warnings and Precautions (5.2) ] Thromboembolism [see Warnings and Precautions (5.3) ] Cholesterol Embolization [see Warnings and Precautions (5.4) ] The most frequently occurring adverse reaction ( > 5%) is bleeding. ( 6 ) To report SUSPECTED ADVERSE REACTIONS, contact Genentech at 1-888-835-2555 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Trials Experience Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. …
Table 3 Combined Safety Outcomes for Studies 1 and 2
| Reaction | Placebo (n= 312) | Activase (n=312) | p-Value Fisher's Exact Test. |
|---|---|---|---|
| All-Cause 90-day Mortality | 64 (20.5%) | 54 (17.3%) | 0.36 |
| Total ICH Within trial follow-up period. Symptomatic intracranial hemorrhage was defined… | 20 (6.4%) | 48 (15.4%) | <0.01 |
| Symptomatic | 4 (1.3%) | 25 (8.0%) | <0.01 |
| Asymptomatic | 16 (5.1%) | 23 (7.4%) | 0.32 |
| Symptomatic Intracranial Hemorrhage within 36 hours | 2 (0.6%) | 20 (6.4%) | <0.01 |
| New Ischemic Stroke (3-months) | 17 (5.4%) | 18 (5.8%) | 1.00 |
Rows and numbers as the label prints them, under its own column headings (the first rows of a longer table where it runs on). A reaction in a trial table is not necessarily caused by the medicine, and trials differ from everyday use.
Source: FDA drug label, Genentech, Inc., effective January 20, 2026 (SPL set c669f77c-fa48-478b-a14b-80b20a0139c2), via openFDA; the full label on DailyMed
What do FAERS reports show?
14,927 reports list alteplase among the medicines taken, each a report of something that happened, not proof the medicine caused it; 3,224 are coded as a death and 3,057 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is. Reports rose sharply in 2024 (2,836, against a median of 849 a year): FAERS counts follow reporting, which news, litigation and label changes can drive, not how often a reaction happens. Of the 20 reactions below, 5 are named by the same term (in US spelling) in the label's adverse reactions, warnings or patient leaflet; a reaction the label does not name may still be there under another word, and a report does not show that the medicine caused it.
Reports received each year
The 25 most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026; reactions as MedDRA preferred terms
What next?
- Alteplase: the full record
- label, generics, price, shortages, recalls
- Report a side effect to the FDA
- MedWatch
- Side effects hub
- the most reported medicines and reactions