What texture is hydroquinone supposed to be?

I bought two hydroquinones recently and started using them for my hyperpigmentation. The expiration date is 2025 but when I used it for two days, it gave me red bumps on my skin. The texture of my hydroquinone is like a paste, a thick white bumpy paste, and water bubbles escaping. It’s as if the paste and water have split. It smoothes out when I rub it into my skin. I opened the other one and it was the same. Also, it has now turned black around the cap. Is this normal?

I don’t know about the products you purchased but HQ commonly has to be shaken up each time you use it. Also about the red bumps… HQ is notorious for irritating. For some, it needs to be started very slowly and used with a lot of hydrating moisturizers!

I have Abbot Melalite forte USP

Sounds like it might have degraded. Some HQ formulations are chalky, others are lotion-like. But water bubbles and water/paste split do not sound normal. The blackness around the cap is oxidation, thus the dark part is no longer stable for use.