Article Text
Abstract
Background Dysphagic patients are at risk of protein-energy malnutrition and dehydration as well as being incompliant to pharmacotherapy. Causes of dysphagia include neurological conditions (such as stroke, dementia, paraplegia/tetraplegia), otorhinolaryngology (ORL) tumours, etc. If parenteral medicines are not available, an oral dosage form of the right consistency should be prepared.
Purpose To present two general formulas for semi-solid dosage forms suitable for dysphagic patients.
Materials and methods A suitable texture of oral preparations and food was predefined by an interdisciplinary focus group from the hospital pharmacy, nutrition support team, ORL physicians and logopedic therapists as being a thick puree or like a milk pudding, being able to keep its shape and not needing mastication. Viscosities of a series of thickened test preparations conforming to these requirements were determined using a parallel plate MCR 302 Anton Paar viscometer.
Results Viscosities of semi-solid preparations suitable for dysphagic patients range between 1600 and 2300 cP (=mPa.s, at 20°). Two general formulations for thickening liquids leading to this viscosity range can be recommended:
Gellan Gum Formula:
Gellan Gum (E 418) is a fermented polysaccharide from Pseudomonas Elodea. It is dissolved at 2(m/V)% in an aqueous drug solution of approximately 50°C, filled into a mould and kept at 2–8°C for 1–2 h for gelification.
Alginate Formula:
Sodium Alginate (E 401) is a polysaccharide from brown algae. A final concentration of 1(m/V)% is dissolved in one half of a calcium-free aqueous drug solution heated to boiling point. This solution I is cooled to 2–8°C for 3–4 h. Solution II consists of calcium lactate 1(m/V)% final concentration dissolved in the second half of the starting drug solution. The gel forms readily by mixing solutions I and II as soon as cross-linking of alginate is induced by calcium.
These preparations yield gel-like textures starting from any aqueous drug solution. The thickened masses can be cut into slices corresponding to a needed dose.
Conclusions Thickened solutions meeting the need of dysphagic patients can be prepared easily using sodium alginate or gellan gum. In contrast to starch-based preparations, they are not sensitive to amylase, thus will not be affected from an undesirable thinning effect with risk of aspiration.
No conflict of interest.