A 22‐year‐old male construction worker in Eastern Samar, Philippines, was bitten on his right leg by a black and yellow snake in the coastal area. Despite receiving a local remedy, he was later brought to the emergency department. Twelve hours post‐bite, careful examination revealed mild bilateral ptosis, with the patient struggling to keep his eyes open, especially during upward gaze (Figure 1A). The bite site showed mild swelling, tenderness, and two fang marks. Although the snake responsible was not conclusively identified, based on the geographical distribution, snake description, and clinical signs, Naja samarensis envenomation was suspected. Intravenous administration of Purified Cobra Antivenom (Research Institute for Tropical Medicine) 1 significantly improved eye‐opening ability within 30 min: the patient could open his eyes fully and sustain eye‐opening (Figure 1B).
FIGURE 1.

(A) Upon admission (12 h after the bite), the patient was unable to keep his eyes open for more than 1 s, particularly during upward gaze. (B) Thirty minutes after the administration of Purified Cobra Antivenom, the patient was able to keep his eyes open for more than 10 s, indicating an improvement in the bilateral ptosis.
Although the literature reports a limited number of cases, Naja samarensis, Samar cobra, is a WHO category I venomous snake in the Philippines. 2 Often, snakebite envenomation diagnosis depends on clinical observations due to limited diagnostic tools. 3 As demonstrated in our image of the probable Naja samarensis case, detection of bilateral ptosis is crucial in recognizing neurological snakebite envenomation. This sign is vital to identify neurotoxic envenomation from various snakes globally, including exotic species.
CONFLICT OF INTEREST STATEMENT
The authors declare no conflicts of interest.
ETHICS STATEMENT
Approval of the research protocol: N/A.
Informed Consent: Informed consent was obtained by the patient.
Registry and the Registration No. of the study/trial: N/A.
Animal studies: N/A.
Aoki Y, Arrieta R, Aquino GJB, Smith C, Agosto LC. Very mild bilateral ptosis following snakebite. Acute Med Surg. 2024;11:e935. 10.1002/ams2.935
DATA AVAILABILITY STATEMENT
Data sharing is not applicable to this article as no new data were created or analyzed in this study.
REFERENCES
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Associated Data
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Data Availability Statement
Data sharing is not applicable to this article as no new data were created or analyzed in this study.
