Medicines and Food

A couple of years ago Janne Graham had the opportunity to attend a pre-conference dinner conducted in association with the Gerontology Conference. The guest speaker Yvonne Coleman, Nutrition Consultants Australia addressed the issues related to medicine/food interactions and participated in a panel with Judith Schmerler a practice nurse and Janne Graham on the topic.

This was Janne’s report from this event:

Although some of the information I heard was familiar it is the first time I have actually been confronted by the depth and breadth of the issues. I hope this summary may be helpful to others.

Medicines can affect nutrition at many points. Food intake can be affected directly by either increased or decreased appetite, or indirectly through adverse reactions such as nausea. Nutrition absorption can be affected directly through inhibition of absorption of nutrients because of a drug or indirectly through such things as altered gastro intestinal tract pH, bacterial overgrowth. Some drugs alter the nutrient metabolism such as phenytoin which increases metabolism and therefore the requirements of Vitamins D,K and folate. Nutrient excretion can sometimes be increased or decreased through medicine use. Of course multiple medication use can confuse all this.

Equally food can alter drug effects. We tend to be aware when we must have medicine with (or without) food. Other issues may be changes in diet, malnutrition which may exacerbate some drug effects, or weight change may need to be taken into account for dosage. Lastly there are the known and unknown food/drug and drug/food interactions.

This field is not well addressed, as many consumers will already know. Often the information we seek is not available, the research and testing has not been done and/or our health professionals do not take these complexities into account. Drug/food interaction advice is often inconsistent and falls into several main groups – advice not provided; foodstuffs contra-indicated, and advice yet to be determined.

Some actions which individual consumers may engage in to focus attention on these matters were touched on in the panel discussion:

• Consumers could contact pharmaceutical companies and ask them about know nutrient issues in relation to their products. There is rarely any information on the CMI because the product is rarely tested or effects measured in relation to trial subjects’ diets. Consistently asking will impact on the companies’ statistics and point to issues for further research. TGA does not require such information and post-market surveillance and complaints procedures are not well geared to pick up such sources of adverse events.
• Report possible inter-relationships to the Consumer Adverse Medicine Event (AME) line (1300 134 237) or seek information from the NPS Medicine Information line (1300 888 763).
• Ask prescribers and pharmacists about food in relation to our medicines.

Consumers and carers will need especially to be alerted to the issues as they may affect older people, in their own home or particularly in residential care. The panel recommended that carers become familiar with the accreditation standards for Commonwealth funded residential care facilities and report recognized breach of food standards to authorities (1800 550 552). There was particular concern about small proportions and inappropriate foods being served (advice: take photos) and variability in the way in which medicines are delivered for people with swallowing difficulties (apparently it is more important to be consistent rather than what vehicle is used–yogurt, cooked apple, jam, honey etc).

Research and knowledge in this field appears to be in its infancy. For instance there is no dedicated research journal dedicated to this field There would seem to be a real opportunity for consumers to drive demand for better information in this arena. There are some clear structural barriers not least of which is the conceptual separation of food and medicines with different regulatory authorities, different manufacturing industries, separate professional groups and little coordinated drive for research. The organized consumer movement is similarly arranged at the national level with CHF more focused on medicines and Choice more on food. Both these organisations and the many consumer and community groups, whether members or not, will be holding through their members a wealth of information on the medicine/food interaction experiences Since the chemicals whether labeled medicine, vitamins, natural products, foods or supplements all integrate in our bodies consumer organisations may be ultimately the only ones in a position to raise the level of awareness.

Janne Graham