Comparison of taste and texture of Metamucil®, Volcolon® and psyllium orange generic

A pleasant taste of a prescription improves patient compliance and adherence.
According to the literature, only 50% of patients who suffer from chronic
diseases adhere to treatment recommendations (1). This results in suboptimal
outcomes (2). There are numerous factors that affect adherence, including
characteristics of the illness, interaction between physician and patient, the
complexity and duration of treatment, side effects of treatment and costs of
treatment (3). Furthermore, medication palatability is also crucial for
adherence. Several studies have addressed the palatability of medication for
different disorders, like hypertension, HIV and Alzheimer*s disease (4-6).
Therefore, pharmaceutical companies pay attention to manufacture more
formulations and add pleasant flavours which may improve the palatability.
Fiber supplements are increasingly used for treatment of chronic constipation
both in adults and children. In the Netherlands several formulas are available
such as Metamucil orange®, Volcolon® en generic psylium orange. These are
effective and save formulas. Little literature is available concerning taste
and laxatives or fibers, although many patients complain about taste and
texture of the preparations. Studies with polyethylene glycol preparations
performed by our research group demonstrated some differences in palatability
between these preparations (7-9).
There are hardly any studies about fibers and taste. The taste is mentioned to
be acceptable; one study compares dried prunes with psylium and concludes there
is no difference in taste experience (10).
In order to improve patient compliance, it is of clinical importance to know
which preparations are the most acceptable to the patient, and use that as
first choice. We hypothese that the taste and palatibility of Metamucil orange®
is preferable.

References:
1. World Health Organisation. Adherence to long term therapies: evidence for
action. 2003.
2. Osterberg L, Blaschke T. Adherence to medication 1. N Engl J Med 2005 August
4;353(5):487-97.
3. Ingersoll KS, Cohen J. The impact of medication regimen factors on adherence
to chronic treatment: a review of literature 1. J Behav Med 2008
June;31(3):213-24.
4. Van der Linden D, Callens S, Brichard B, Colebunders R. Pediatric HIV: new
opportunities to treat children 1. Expert Opin Pharmacother 2009
August;10(11):1783-91.
5. Meier CM, Simonetti GD, Ghiglia S, Fossali E, Salice P, Limoni C et al.
Palatability of angiotensin II antagonists among nephropathic children 1. Br J
Clin Pharmacol 2007 May;63(5):628-31.
6. Yan YD, Woo JS, Kang JH, Yong CS, Choi HG. Preparation and evaluation of
taste-masked donepezil hydrochloride orally disintegrating tablets 1. Biol
Pharm Bull 2010;33(8):1364-70.
7. Felt-Bersma R.J., Kooyman G., Kuipers E.J. Colonic lavage prior to
colonoscopy: comparable outcomes of two polyethylene-glycol preparations and a
sodium-phosphate solution. Ned Tijdschr Geneeskd. 2004 Jan 24; 148 (4): 181-5
8. Szojda MM, Mulder CJ, Felt-Bersma RJ. Differences in taste between two
polyethylene glycol preparations.J Gastrointestin Liver Dis. 2007;16(4):379-81
9. Lam TJ, Mulder CJ, Felt-Bersma RJ. Differences in taste between three
polyethylene glycol preparations: a randomized double-blind study. Patient
Prefer Adherence. 2011;5:423-6.
10. Yan YD, Woo JS, Kang JH, Yong CS, Choi HG. Preparation and evaluation of
taste-masked donepezil hydrochloride orally disintegrating tablets 1. Biol
Pharm Bull 2010;33(8):1364-70.

Comparison of 1. taste and 2. texture/palatability of Metamuci orangel®,
Volcolon® and generic orange psyllium.

It is a double blind, randomized, crossover study.

All healthy volunteers will try the 3 different formulas. After swallowing the
first formula, the mouth will be rinsed with water. Then the second formula
will be tried, after rinsing the mouth again the third formula will be tried.
Every time after tasting a formula, the questionnaire is filled in, before
starting with the next formula. The maximum intake is 3 x 25 ml (75 ml), this
is 37,5% of one dosage advised quantity of fibre. The sequence in which the
formulas are tasted is randomized.

Preparations and dosage

Each sachet needs to be solved in a glass of water. This matches
(approximately) 200 ml. During the study the volunteers will taste 3 x 25 ml of
water. This matches 37,5% of one dosage. The average intake of psyllium fibers
is 1-3 sachets a day.
Dosage if the different products:
- Volcolon sugar free (Dutch name: Volcolcolon suikervrij): 1 sachet contains 4
g powder
o 980mg/g psyllium fibers x 4 g per sachet = 3.92 g psyllium fibers/sachet
o So 25 ml contains 0.490 g psyllium fibers
- Metamucil Orange: 1 sachet contains 3.4 g psyllium fibers
o So 25 ml contains 0.425 g psyllium fibers
- Psyllium Orange: 1 sachet contains 3.25 g psyllium fibers
o So 25 ml contains 0.406 g psyllium fibers

These three products are the most used products for each brand (Metamucil
orange, Volcolon and generic orange). This leads to the greatest coverage of
the three brands in the Netherlands. The volunteers will swallow 25 ml of each
product, three in total. This leads to an intake of 1.32 g (0.490 g + 0.425 g +
0.406= 1.32 g) psyllium fibers. According to the Dutch Board of Health (in
Dutch: Gezondheidsraad) the average intake of fibers should be between 30 and
40 g a day. So, the volunteers will swallow approximately 4% (3.3 * 4.4%) of
the advised intake of fibers. Therefore, we do not expect any problems when the
volunteers swallow these products.

The maximum intake is 3 x 25 ml (75 ml), this is 37,5% of one dosage advised
quantity of fibre. Therefore, we do not expect any problems when the volunteers
swallow these products.