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5. Effect if any of the drug on the consistency or other features of the semisolid base
(Incompatibility)

6. Characteristics of the surface to which it is applied
▪ Never use PEG base for mucous membrane like eye and use fatty base as PEG base
cause dehydration and irritation
▪ For hairy area and scalp, use low viscosity product and avoid thick base like Vaseline
▪ Use an easily spreadable preparation for highly inflamed skin to avoid pain during
application and preferred to give cooling effect
▪ a cream is applied to weeping or oozing surfaces, and a lotion is applied to
intertriginous areas or where friction may occur

Novel advances is semisolid dosage forms:

• Mainly in creams and gels
• Use of nanotechnology as nanoemulsions, solid lipid nanoparticles
• Use of microspheres (e.g. Albumin microspheres for Vitamin A delivery in creams)
• TIMERx is a controlled release technology used in gel formulations (it is a hydroplillic

complex which forms a sustained release complex upon compression)
• Delivery of monoclonal antibodies in semi solid dosage forms (e.g Lysostaphin gel for

intranasal administration)

Evaluation of semisolid dosage forms:

Why do we need to evaluate semisolids?
• To ensure that commercialized drug products are safe and effective at release and during
shelf life.
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