A comparison of various methods for the detection of isoniazid and its metabolites in urine

An enquiry into the attitudes of South Indian patients to the coloration of their urine by rifampicin

This report enquiring into patients' attitudes to their urine being coloured by rifampicin has shown that many of them regarded it as evidence of the potency of their medicine or of the elimination of the disease. Attention is drawn to the value of the coloured urine as a reminder to patients whether or not they have taken their due dose of rifampicin-containing medicine.

A sensitive urine-test method for monitoring the ingestion of isoniazid

A method is described for monitoring the ingestion of isoniazid based on detecting its metabolites, isonicotinic acid, and isonicotinylglycine in the urine. The sensitivity of the method is high so that reliably positive results were obtained up to about 24 hours after the ingestion of 100 mg isoniazid. The method should facilitate monitoring the taking of isoniazid by tuberculosis patients and the use of isoniazid as a marker for assessing the regularity with which other drugs prescribed for self-administration are actually ingested.

The use of isoniazid as a marker to monitor the self-administration of medicaments

1. Isoniazid was used as a marker to monitor the regularity of drug self-administration in a trial of chemoprophylaxis against natural influenza infection. Two hundred and sixty-two volunteers were treated for five weeks with a synthetic isoquinoline compound (U.K. 2371) or a matching placebo. 2. Five marker tablets containing isoniazid (150 mg) were incorporated into each regimen and their ingestion monitored by testing for acetylisoniazid in the urine. 3. Positive evidence of marker tablet consumption was obtained on 75% of the occasions on which urine samples were requested. The results obtained among the volunteers from each treatment group who returned urine specimens as requested (92%) indicated that they had swallowed at least 81% of their prescribed tablets. 4. The findings of the study suggest that when used in this way isoniazid is a very suitable compound for use on a few occasions for monitoring the self-administration of drugs in clinical trials.