IPSILATERAL HERPES ZOSTER OPTHALMICUS; GENERALIZED WEAKNESS; This spontaneous report was received from literature: . This report concerned a 42 year old male of an unspecified race and ethnicity. The objective of this study was to describe Ipsilateral HZO (Herpes Zoster Ophthalmicus), an opthalmological emergency of herpes zoster (HZ) seen post Covid-19 vaccination in healthy young adults.  The patient's height, and weight were not reported. The patient's past medical history included: admitted chickenpox at the age of 10, and concurrent conditions included: asthma. The patient denied any sick contacts, recent emotional or physical stress, recent travel, or steroid usage in the past one year. The patient received Covid-19 vaccine ad26.cov2.s (suspension for injection, route of admin not reported, batch number: unknown and expiry: unknown) dose, start therapy date were not reported, frequency time 1 total administered at left arm for prophylactic vaccination. The batch number was not reported and has been requested. No concomitant medications were reported. On an unspecified date, post COVID-19 vaccination the patient experienced generalized weakness for two days. One week after receiving the vaccination, the patient noticed that skin lesions started appearing as small pimples on the left side of his forehead that were associated with burning pain and itching. The lesions had then rapidly progressed to the left side of the scalp, the tip of the nose, and the left upper eyelid. Associated symptoms were watery discharge from the eyes and blurred vision. He denied having any other complaints. On an unspecified date, the patient presented to the emergency room with the above mentioned complaints. Laboratory data included: blood pressure which was found to be 151/89, body temperature was found to be afebrile, heart rate was found to be 93, hemoglobin (NR: 13.5 - 17.5) was found to be 15 g/dL. Physical examination revealed erythematous grouped vesicles on the left side of the patient's forehead, left upper eyelid, left side of the scalp and tip of his nose. The left eyelid appeared to be edematous with conjunctival injection and watery discharge, with no visible corneal endothelial decompensation. There was restricted ocular movement noticed due to edema of his upper eyelid. Visual acuity test was also found to be limited. Platelet count (NR: 150000 - 450000) was found to be 274000 cells/microL, Respiratory rate was 18, and White blood cells (NR: 4500 - 11000) were 5.50 cells/microL.  Based on clinical examination findings, the diagnosis of ipsilateral HZO  (Herpes Zoster Ophthalmicus) was made. He was started on systemic antiviral (antivirals for systemic use) and antiviral eye drops, which halted the progression of vesicles and improved his vision. The action taken with Covid-19 vaccine ad26.cov2.s was not applicable. The patient recovered from generalized weakness, and the outcome of ipsilateral herpes zoster opthalmicus was not reported. The authors emphasized on the awareness that must be created among physicians, as well as the general public by reporting any associations with the COVID-19 vaccine and HZ (Herpes zoster) to CDC. It was recommended that immunocompromised individuals greater than 50 years of age be vaccinated against HZ (Herpes zoster). Early recognition and antiviral usage can halt the progression of the disease and thus prevent debilitating complications. This report was serious (Other Medically Important Condition).; Sender's Comments: V0: 20210832958-Covid-19 vaccine ad26.cov2.s-ipsilateral herpes zoster ophthalmicus. This event(s) is considered unassessable. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event(s).