Table 5.

Selected CL drug delivery experiments investigating anti-allergy agents [16,155].

Drug	Method Used	Loading Conditions	Results	Ref.
ANTIHISTAMINES AND MAST CELL STABILISERS
Cromolyn sodium	Unmodified commercial hydrogel and silicone hydrogel materials	20 mg/mL solution for 50 h	In vitro: Alphafilcon A (1147 ± 146 μg/lens).	Karlgard 2003 [160]
Ketotifen fumarate	Unmodified commercial hydrogel and silicone hydrogel materials	2.5 mg/mL solution or 24 h	In vitro: Etafilcon (284.5 ± 29.8 μg/lens) Balafilcon A (227.6 ± 14.7 μg/lens).	Soluri 2012 [172]
Ketotifen fumarate	Soaking Combined acrylic acid, acrylamide, N-vinyl 2- pyrrolidinone and polyethylene glycol (200) dimethacrylate molecularly imprinted pHEMA gels	Soaking in ‘concentrated’ ketotifen solutions until equilibrium	In vitro: Increased ketotifen loading into gels 6- to 8-fold. 8% of the total amount of drug released after 4 days. Presence of lysozyme: further extended-release times 5-fold. In vivo: Imprinted contact lens: increase 4 and 50 times compared to nonimprinted lenses and eye drops, respectively.	Venkatesh 2007 [173] Ali 2007 [174] Venkatesh 2008 [175] Tieppo 2012 [99]
Ketotifen fumarate	Model DMA, MA-PDMS-MA, TRIS, hydrogel contact lenses	1.945 mg/mL solutions for five days	In vitro: hydrophilic phases exhibited faster release. In vivo: 19.53 μg/mL in tear film after 24 h of lens wearing.	Xu 2011 [176]
Olopatadine hydrochloride	Combined acrylic acid, acrylamide, 2- acrylamide-2-methyl- propane sulfonic acid and benzyl methacrylate molecularly imprinted pHEMA materials	0.2 or 10 mg/mL solutions for 20 days	In vitro: Sustain release for upward of 24 h.	González-Chomon 2016 [177]

DMA: N, N-dimethyl acrylamide, MA-PDMS-MA: methacrylated polydimethylsiloxanes, pHEMA: poly-2-hydroxyl ethyl methacrylate, TRIS: tris(trimethyl siloxy) silyl-propyl methacrylate.