MD, PhD, FMedSci, FSB, FRCP, FRCPEd

essential oil

It has been reported that ‘Boots the Chemist’ have filed several legal complaints against The Guardian in relation to articles published by the paper in relation to its April 2016 investigation. The Guardian articles in question alleged that Boots, the UK’s largest pharmacy chain, had placed undue pressure on its pharmacists to perform medicines use reviews so that it could claim the maximum payments possible from the NHS. In other words, The Guardian implied that Boots was trying to get more money from our NHS than might have been due.

Personally, I am always uneasy when I hear that someone takes legal action on such matters. I think that legal complaints of such a nature can turn out to be counter-productive, both in general and in this particular instance.

Why?

There could be several reasons. For instance, such actions might give someone the idea of filing complaints against Boots. I am sure it is not difficult to find reasons for that.

In the realm of alternative medicine, for example, someone might question whether selling homeopathic remedies in Boot’s section ‘pharmacy and health’ is not misleading. These remedies might be seen by a naïve customer as masquerading as medicines. As readers of this blog know all too well, they do not, in fact, contain anything (other than lactose) that has any pharmacological activity. Therefore Boots should best market them in the category of ‘confectionary’.

One might even suspect that Boots are fully aware of all this. After all, a spokesperson for the company stated years ago during a parliamentary inquiry: “I have no evidence to suggest that they [homeopathic remedies sold by Boots] are efficacious …”

And it is also not the first time that Boots have been challenged for selling products they know to be placebos. This is what The Guardian reported in 2008 about the issue: “Ernst accuses the company [Boots] of breaching ethical guidelines drawn up by the Royal Pharmaceutical Society of Great Britain, by failing to tell customers that its homeopathic medicines contain no active ingredients and are ineffective in clinical trials.”

A similar void of evidence also applies to Boot’s wide range of Bach Flower Remedies and aromatherapy oils.

Or am I wrong?

Perhaps Boots want to post links to the evidence in the  comment section below?

I am always keen to learn and only too happy to change my mind in view of new, compelling evidence!

Boots also sell a very wide range of herbal medicines, and here the situation is quite different: herbal medicines actually contain molecules that might have pharmacological effects, i. e. they might heal or might harm you. And many of these products imply indications for which they should be taken. I will pick just one example to explain: HERBAL SLIM AID.

Yes, you are absolutely correct – this product is (according to its name) not for gaining weight, it’s for reducing it. Each coated tablet contains 45 mg of extract (as dry extract) from Bladderwrack thallus (Fucus vesiculosus L.) (5:1) (equivalent to 225 mg of Fucus) Extraction solvent: water, ,30 mg Dandelion Root (Taraxacum officinale Weber ex Wigg), 27 mg of extract (as dry extract) from Boldo leaf (Peumus boldus Molina) (4-6:1) (equivalent to 108-162 mg of Boldo leaf) Extraction solvent: Methanol 70% v/v, 10 mg Butternut Bark (Juglans cinerea L.).

Now, I thought I know quite a bit about herbal slimming aids, after all, we had a research focus on this topic for several years and have published about a dozen papers on the subject. But oddly, I cannot remember that this mixture of herbs has been shown to reduce body weight.

Perhaps Boots want to post evidence for the efficacy and safety of this product as well?

I certainly hope so, and I would instantly withdraw any hint of a suspicion that Boots are selling unproven or disproven medicines.

Where is all this going?

I have to admit that am not entirely sure myself.

I suppose all I wanted to express was that it might be unwise to throw stones when one is sitting in a glass-house – a cliché, I know, but it’s true nevertheless.

 

 

 

CONFLICTS OF INTEREST:

None [except I don’t like those who easily take legal action against others]

AROMATHERAPY is one of the most popular alternative therapies. The experience is usually pleasant enough, but what are the risks? None!!! At least this is what the therapists would claim. But is this true? Perhaps not. According to a recent press-release, the risks might be considerable.

Officials with the Tennessee Poison Control Center (TPC) are warning that they are seeing an increasing number of toxic exposures, mostly involving children, to essential oils used in aromatherapy. The TPC says the number of essential oil exposures doubled between 2011 and 2015, and 80 percent of those cases involved children. The primary route of poisoning is by ingestion, but also occurs with excessive or inappropriate application to the skin. Children are at risk because their skin easily absorbs oils and because they may try to ingest essential oils from the container.

“Tea tree oil is commonly cited, and most of those cases are accidental ingestions by children.” said Justin Loden, PharmD, certified specialist in Poison Information (CSPI) at TPC. Most essential oils have a pleasant smell but bitter taste, so children easily choke on them and aspirate the oil to their lungs, Loden said.

Several essential oils such as camphor, clove, lavender, eucalyptus, thyme, tea tree, and wintergreen oils are highly toxic. All of the oils produce oral and throat irritation, nausea, and vomiting when ingested. Most essential oils either produce central nervous system (CNS) stimulation, which results in agitation, hallucinations, delirium, and seizures or CNS depression, which results in lethargy and coma. Other toxic effects include painless chemical burns, hypotension, acute respiratory distress syndrome, acute liver failure, severe metabolic acidosis, and cerebral edema depending on which essential oil is in question.

Tennessee Poison Center Tips for using essential oils

  • Safely using and storing essential oils is extremely important
  • Use essential oil products ONLY for their intended purpose.
  • Use only the amount stated on the label/guide.
  • Do not swallow an essential oil unless the label says to do so.
  • Do not use a product on the skin unless the label says to do so.
  • Do not leave the product out (i.e. as a pesticide) unless the label says to do so.
  • If you have bottles of essential oils at home, keep them locked up, out of sight and reach of children and pet at all times. Children act fast, so do poisons.

Many will think that this is alarmist – but I don’t. In fact, in 2012, I published a systematic review aimed at critically evaluating the evidence regarding the adverse effects associated with aromatherapy. No, it was not funded by ‘BIG PHARMA’ but by THE ROYAL COLLEGE OF PHYSICIANS, LONDON.

Five electronic databases were searched to identify all relevant case reports and case series. Forty two primary reports met our inclusion criteria. In total, 71 patients experienced adverse effects of aromatherapy. Adverse effects ranged from mild to severe and included one fatality. The most common adverse effect was dermatitis. Lavender, peppermint, tea tree oil and ylang-ylang were the most common essential oils responsible for adverse effects.

At the time, we concluded that aromatherapy has the potential to cause adverse effects some of which are serious. Their frequency remains unknown. Lack of sufficiently convincing evidence regarding the effectiveness of aromatherapy combined with its potential to cause adverse effects questions the usefulness of this modality in any condition.

I might add – before the therapists start making comments – that, yes, aromatherapy is still dimensions safer than many conventional treatments. But remember: the value of a therapy is not determined by its safety but by the risk/benefit balance! And what are the proven benefits of aromatherapy, I ask you.

Of all alternative treatments, aromatherapy (i.e. the application of essential oils to the body, usually by gentle massage or simply inhalation) seems to be the most popular. This is perhaps understandable because it certainly is an agreeable form of ‘pampering’ for someone in need of come TLC. But is aromatherapy more than that? Is it truly a ‘THERAPY’?

A recent systematic review was aimed at evaluating the existing data on aromatherapy interventions as a means of improving the quality of sleep. Electronic literature searches were performed to identify relevant studies published between 2000 and August 2013. Randomized controlled and quasi-experimental trials that included aromatherapy for the improvement of sleep quality were considered for inclusion. Of the 245 publications identified, 13 studies met the inclusion criteria, and 12 studies could be used for a meta-analysis.

The meta-analysis of the 12 studies revealed that the use of aromatherapy was effective in improving sleep quality. Subgroup analysis showed that inhalation aromatherapy was more effective than aromatherapy applied via massage.

The authors concluded that readily available aromatherapy treatments appear to be effective and promote sleep. Thus, it is essential to develop specific guidelines for the efficient use of aromatherapy.

Perfect! Let’s all rush out and get some essential oils for inhalation to improve our sleep (remarkably, the results imply that aroma therapists are redundant!).

Not so fast! As I see it, there are several important caveats we might want to consider before spending our money this way:

  1. Why did this review focus on such a small time-frame? (Systematic reviews should include all the available evidence of a pre-defined quality.)
  2. The quality of the included studies was often very poor, and therefore the overall conclusion cannot be definitive.
  3. The effect size of armoatherapy is small. In 2000, we published a similar review and concluded that aromatherapy has a mild, transient anxiolytic effect. Based on a critical assessment of the six studies relating to relaxation, the effects of aromatherapy are probably not strong enough for it to be considered for the treatment of anxiety. The hypothesis that it is effective for any other indication is not supported by the findings of rigorous clinical trials.
  4. It seems uncertain which essential oil is best suited for this indication.
  5. Aromatherapy is not always entirely free of risks. Another of our reviews showed that aromatherapy has the potential to cause adverse effects some of which are serious. Their frequency remains unknown. Lack of sufficiently convincing evidence regarding the effectiveness of aromatherapy combined with its potential to cause adverse effects questions the usefulness of this modality in any condition.
  6. There are several effective ways for improving sleep when needed; we need to know how aromatherapy compares to established treatments for that indication.

All in all, I think stronger evidence is required that aromatherapy is more that pampering.

ENOUGH SAID?

My aim with this blog is to eventually cover most of the 400 or so different alternative therapies and diagnostic techniques. So far, I have focused on some of the most popular modalities; and this means, I have neglected many others. Today, it is time, I think, to discuss aromatherapy, after all, it is one of the most popular forms of alternative medicine in the UK.

Aromatherapists use essential oils, and this is where the confusion starts. They are called “essential” not because humans cannot do without them, like essential nutrients, for instance; they are called “essential” because they are made of flower ESSENCES. The man who ‘discovered’ aromatherapy was a chemist who accidentally had burnt his hand and put some lavender essence on the burn. It healed very quickly, and he thus concluded that essential oils can be useful therapeutics.

Today’s aromatherapists would rarely use the pure essential oil; they dilute it in an inert carrier oil and usually apply it via a very gentle massage to the skin. They believe that specific oils have specific effects for specific conditions. As these oils contain pharmacologically active ingredients, some of these assumptions might even be correct. The question, however, is one of concentration. Do these ingredients reach the target organ in sufficient quantities? Are they absorbed through the skin at all? Does smelling them have a sufficiently large effect to produce the claimed benefit?

The ‘acid test’ for any therapeutic claim is, as always, the clinical trial. As it happens a new paper has just become available. The aim of this randomised study was to determine the effects of inhalation aromatherapy on pregnant women. Essential oils with high linalool and linalyl acetate content were selected and among these the one preferred by the participant was used. Thirteen pregnant women in week 28 of a single pregnancy were randomly assigned into an aromatherapy and a control group. The main outcome measures were several validated scores to assess mood and the heart-rate variability. The results showed significant differences in the Tension-Anxiety score and the Anger-Hostility score after aromatherapy. Heart rate variability changes indicated that the parasympathetic nerve activity increased significantly in the verum group. The authors concluded that aromatherapy inhalation was effective and suggest that more research is warranted.

I have several reasons for mentioning this study here.

1st research into aromatherapy is rare and therefore any new trial of this popular treatment might be important.

2nd aromatherapy is mostly (but not in this study) used in conjunction with a gentle, soothing massage; any outcome of such an intervention is difficult to interpret: we cannot then know whether it was the massage or the oil that produced the observed effect. The present trial is different and might allow conclusions specifically about the effects of the essential oils.

3rd the study displays several classic methodological mistakes which are common in trials of alternative medicine. By exposing them, I hope that they might become less frequent in future.

The most obvious flaw is its tiny sample size. What is an adequate size, people often ask. This question is unfortunately unanswerable. To determine the adequate sample size, it is best to conduct a pilot study or use published data to calculate the required number of patients needed for the specific trial you are planning. Any statistician will be able to help you with this.

The second equally obvious flaw relates to the fact that the results and the conclusions of this study were based on comparing the outcome measures before with those after the interventions within one intervention group. The main reason for taking the trouble of running a control group in a clinical trial is that the findings from the experimental group are compared to those of the control group. Only such inter-group comparisons can tell us whether the results were actually caused by the intervention and not by other factors such as the passage of time, a placebo-effect etc.

In the present study, the authors seem to be aware of their mistake and mention that there were no significant differences in outcomes when the two groups were compared. Yet they fail to draw the right conclusion from this fact. It means that their study demonstrated that aromatherapy inhalation had no effect on the outcomes studied.

So, what does the reliable trial evidence on aromatherapy tell us?

A clinical trial in which I was involved failed to show that it improves the mood or quality of life of cancer patients. But one swallow does not make a summer; what do systematic reviews of all available trials indicate?

The first systematic review was probably the one we published in 2000. We then located 12 randomised clinical trials: six of them had no independent replication; six related to the relaxing effects of aromatherapy combined with massage. These 6 studies collectively suggested that aromatherapy massage has a mild but short-lasting anxiolytic effect. These effects of aromatherapy are probably not strong enough for it to be considered for the treatment of anxiety. We concluded that the hypothesis that it is effective for any other indication is not supported by the findings of rigorous clinical trials.

Since then several other systematic reviews have emerged. We therefore decided to summarise their findings in an overview of all available reviews. We searched 12 electronic databases and our departmental files without restrictions of time or language. The methodological quality of all systematic reviews was evaluated independently by two authors. Of 201 potentially relevant publications, 10 met our inclusion criteria. Most of the systematic reviews were of poor methodological quality. The clinical subject areas were hypertension, depression, anxiety, pain relief, and dementia. For none of the conditions was the evidence convincing. Our conclusions therefore had to be cautious: due to a number of caveats, the evidence is not sufficiently convincing that aromatherapy is an effective therapy for any condition.

Finally, we also investigated the safety of aromatherapy by assessing all published data regarding adverse effects. Forty two primary reports met our inclusion criteria. In total, 71 patients had experienced adverse effects after aromatherapy which ranged from mild to severe and included one fatality. The most common adverse effect was dermatitis. Lavender, peppermint, tea tree oil and ylang-ylang were the most common essential oils responsible for adverse effects. We concluded that aromatherapy has the potential to cause adverse effects some of which are serious. Their frequency remains unknown.

And what is the conclusion of all this? To me, it seems fairly straight forward: Aromatherapy is not demonstrably effective for any condition. It also is not entirely free of risks. Its risk/benefit profile is thus not positive which can only mean that it is not a useful or recommendable treatment for anybody who is ill.

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