Hello. Thanks for updating your query here.
Penile injection therapy with Alprostidil, (which has vasodilator properties) is an FDA approved medication for people who insist for immediate erection and for those with broad range of medical conditions. The drug is delivered via injection in to the vessels of penis and the patient is educated to inject it to the side of the penis. In a clinical study , 80% of men treated with this therapy achieved firm erections. It would take 5 20 minutes to attain an erection. The most common side effect is pain or dull ache at the site of injection.
The only possibility that your colleague being able to maintain erection even after ejaculation is, the use of penile injections. The drug that is injected takes some time to get cleared from that area, in which time it produces (maintains) erections.
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