Promethazine hydrochloride tablets commercially available at Libyan market. It is use as antihistaminic tablet, strong seddative, reduce motion sickness, and has antiemetic and anticholinergic properties. It works as competitive histamine (H₁) and alpha -adrenergic receptor antagonist. This study aims to measure the quality of those promethazine tablets and the released active ingredient. Material and Methods: Promethazine Hydrochloride 25mg tablets purchased from pharma international company (drug distributer of Remedica), Benghazi-Libya. The tests used in this study were the following: hardness, friability, weight uniformity, content uniformity, disintegration, and dissolution test. Those tests certified at the British pharmacopeia (Bp). Results: The hardness test shows a hardness value of 6.76kg. This means that the tablet meets the pharmacopeial requirements. The promethazine tablet with 0.401cm thickness(h) and 0.820cm in diameter (r) requires a force of 13.465kgcm (T.s) to be broken. The results obtained comply with the British pharmacopeia1998. The promethazine tablet has friability of 0.032%, which does not comply with the British pharmacopeia1998. The promethazine tablets have weight uniformity of 209.3mg. Which means that the tablet is uniform in weight and accepted according to the pharmacopeial limits. Disintegration test shows that the tablets completely disintegrated after 1.84min. The content uniformity test shows results within a pharmacopeial limit. Additionally, the dissolution test results were out of the pharmacopeial range. Conclusion: The promethazine tablets deviate from some pharmacopeial tests, which emphasized the need of continuous investigations to the antihistaminic tablets present at Libyan market to ensure the quality of medicines for the Libyan patients.