INSIGHT — The Consumer Magazine (March-April 2007) has published the findings of its in-house comparative product testing laboratory on 23 brands (5 molecules) of anti-hypertensive tablets. The brands tested are sold countrywide.
People understand the increase in blood pressure and attribute it to their daily diet. The increase in blood pressure is also symbollic of hypertension. Among other things, the increase in blood pressure may be due to physical exercise, stress, anxiety, emotional changes. If hypertension is ignored, the complications arising as a result may cause severe disability, more than other types of diseases. The complications may lead even to death. Patients of hypertension may be treated with change of lifestyle or prescribed anti-hypertensive tablets or both.
So we decided to test these life-saving drugs.
It would be a relief to know that all the brands tested complied with the Standards specified in the British, Indian, and US Pharmacopoeia.
Two Kinds of Drugs
We selected single molecule and combination tablets of anti-hypertensive drugs. Mostly combination drugs are preferred and prescribed by doctors now.
The molecules tested were atenolol, enalapril, lisinopril. Atenolol is a beta-blocker, enalapril and lisinopril are ACE inhibitors. Enalapril maleate with hydrochlorothiazide and atenolol with chlorthalidone were the combination drugs tested. Enalapril maleate with hydrochlorothiazide is ACE inhibitor with thiazide and atenolol with chlorthalidone is beta blocker with calcium channel blocker.
All the drugs were tested as per their respective pharmacopoeia. The combination product of atenolol and chlorthalidone was marked as BP (British Pharmacopoeia) but was tested as per the US Pharmacopoeia to provide more information to consumers. The BP does not provide for the dissolution test mentioned in the USP.
All the tablets were tested for four basic parameters - identification, assay, uniformity of weight and disintegration. We also tested the combination product atenolol with chlorthalidone for dissolution as per the US Pharmacopoeia.
All the brands passed the tests except Atecard-D. The drug manufactured by Dabur passed all the tests except for dissolution. Atecard-D did not conform to the dissolution test mentioned in the US Pharmacopoeia. Less dissolution means that the effect will be slower and the absorption of the drug in the blood will be less. Except Atecard-D, other brands marked BP but tested as per USP, passed all the tests, including the dissolution test.
As all the brands complied with the Standards, a major criterion for preferring one brand to another is the price. Zestril (2.5 mg) manufactured by Astra Zeneca Pharma was found costlier than the other brands of Lisinopril.
This test is done to identify the active ingredient in the drug.
The test for assay is done to find out the actual amount of active ingredient in the tablet and whether it is the same as what is labelled. This is carried out on 20 samples of each brand.
Uniformity Of Weight
This test is done to check the individual variation of the weight from the average weight of the dosage unit. This also gives an idea of the uniformity of distribution of the material before the preparation of the tablets.
A tablet needs to break down into small particles or disintegrate so that it is ready for absorption within a specific time period. This test checks whether a tablet disintegrates within a fixed time limit.
Uniformity Of Content
This test determines whether the actual amount of active ingredient is present in a single dose, i.e. a single tablet.
The dissolution test measures the actual release of the drug from the tablet which is an essential step in drug availability of the body.
As a policy, the test results are conveyed to all the manufacturers for their views and comments. All manufacturers receive the results of their own product only. Details of the Test Report have been published in the March-April 2007 issue of INSIGHT.
Date : 13/04/2007
Place : Ahmedabad
INSIGHT — The Consumer Magazine
Annexure : Test Results of Anti-Hypertensive Tablets
We tested 23 brands (5 molecules) of anti-hypertensive tablets, all of which are national brands. The atenolol tablets which had 25 mg strength were Atenova, Hipres, Betacard, Atepark, Tenormin, Tensicard, Atenex and Atecard. The enalapril maleate tablets of 2.5 mg were Envas, Enam, Enapril and Enace. The lisinopril 2.5 mg tablets were Listril, Lipril, Cipril and Zestril. The combination products were Normace-D, Enapril-HT, Enace-D and Envas H in the enalapril maleate with hydrochlorothiazide category and it was Tenoric-50, Tenoclor-50 and Atecard-D in the combination of atenolol with chlorthalidone.