High risk of serious developmental disorders if exposed in womb (up to 30-40% risk, including 5x higher risk of autism) and congenital malformations (10%), including:
Spina bifida
face/skull malformations, including cleft lip/palate
Limb, heart, kidney, genital abnormalities
Deafness
In boys, pre-clinical data on transgenerational risks, and animal studies suggesting infertility.
Oral Valproate must not be started in new patients (male or female) younger than 55 years, unless two specialists independently consider and document that there is no other effective or tolerated treatment, or there are compelling reasons that the reproductive risks do not apply.”
Systematic review – just 0.21% of unselected general paediatric outpatients exhibit positive antibiotic allergy tests, and only 6.8% of those with suspected allergy test positive.
No evidence to support using skin prick testing. Intradermal testing has high false positive rate (64-67% for penicillin and clarithromycin). Caubet did oral provocation test (OPT) regardless of intradermal result to beta lactam, NNT=11 to avoid one OPT! [Ped All Immun 2015 ]. OPT reactions tend to be cutaneous and mild, usually more than 1hr post administration.
Where reaction is severe but non-immediate, eg Stevens Johnson syndrome, Toxic Epidermal Necrolysis (TEN), Drug Rash with Eosinophilia and Systemic Symptoms (DRESS), care needs to be taken with investigation, but studies have reported intradermal and OPT without unsafe adverse effects. If reaction is anaphylaxis with first dose, then OPT contraindicated.
Wide variety in regimens. Suggests 1-5 incremental doses of amoxicillin for mild reactions (timing not specified), giving cumulative dose appropriate to child, then continuing for 3 days. Skin testing may be appropriate for severe reactions according to risk:benefit balance. Check asthma well controlled, no antihistamines. Warn that low risk of false negative result (absent co-factors) and low risk of re-sensitization.
Macy article says any rash can have OPT! 5mm pos SPT for penicilloyl-polylysine has good negative predictive value for anaphylaxis with OPT. Recommends 5 days amoxicillin.
[Ann Allergy Asthma Immunol 121(2018):523−529]
Mirakian article suggests SPT for all immediate reactions! Split dose challenges, with a week between first and second doses!
For non immediate reactions (1-72hrs), OPT confirmed in 59%, ID less than 40%.
6 studies showing that benign reactions (ie witnessed macpap or urticarial, no pain/burning, <50% skin surface etc) do not need skin testing. Geneva have done more than 800 straight to OPT. New EAACI guidelines in press.
If delay in reaction is unclear, assume immediate. SPT vs amoxicillin, PPL, MDM. IgE vs BPL. 0.04ml ID volume. Note different reference ranges! See Brockour, Allergy 13
Recent letter claimed OPT after skin test was “unnecessary, dangerous, unethical”! But 30-100% false negatives!
Clavulanate allergy described.
Test sensitivity falls more than 4/12 after episode, ideally do within 4-6/52????
Basophil activation test using flow cytometry looking promising for IgE mediated drug reactions. EAACI interest group working on Drug Allergy Passport.
See NICE CG224 (refers then to CG111 (pyelonephritis) and CG109 (lower tract UTI)): Under 3 months get IV treatment. Else 3 days oral treatment if lower tract, 7-10 days oral for upper tract. IV for vomiting, unable to take oral or severe illness (but also says underlying known anomalies should influence choice) 2-4 days IV then oral for total of 10 days (!). No preference between cefuroxime, ceftriaxone and gentamicin. Upper tract defined as fever else loin pain/tenderness
Cochrane review concluded that 2-4 day course of oral antibiotic is as effective as a 7-14 day course in the treatment of lower-tract UTIs in children. PMID 12535494The majority of febrile infants with UTI have nuclear scan evidence of pyelonephritis, suggesting that infants should not receive short course treatment.
Also concluded that for pyelonephritis oral antibiotics are as effective as the combination of parenteral followed by oral antibiotics. Based on:
Hoberman’s RCT children under 2 with fever and UTI (n=300) – oral cefixime for 2 weeks as good as IV: no difference in defervescence, reinfection, scarring at 6 months (and much cheaper!). Severely ill excluded (eg CRT>3sec) – only 3! Funny group though, mean age of 8 months, 90% female, and a low scarring rate (15%). Pediatrics 99 Vol. 104: 79, Hoberman A.
Montini Multicentre RCT non-inferiority (n=502, 1/12 to 7yrs). Oral co-amoxiclav for 10 days equivalent to ceftriaxone for three days followed by oral in terms of DMSA scars, time to defervescence. BMJ 2007; 335:386-8
Crucial that oral antibiotics are not vomited, of course.
Gauthier et al treated infants and toddlers with febrile UTIs as outpatients using a single daily dose of intravenous gentamicin until the children were afebrile for at least 24 hours, after which oral amoxicillin (!) was given until the urinary culture report was available. Successful in three quarters. Current Opinion in Pediatrics. 18(2):134-8, 2006
1/3 of UTI E coli resistant to trimethoprim, 2/3 if underlying renal abnormality. 61% of women with UTIs and resistant organisms do not reconsult! So should we use community surveillance to guide prescribing rather than individual culture and sensitivity?
UTI prophylaxis did not reduce recurrent infection (n=611). But lower rate (12%) reported than might be expected. Higher resistance rates are seen in recurrent infections, which could be anticipated (JAMA 2007;298;179)
Who needs one? Anyone at risk of anaphylaxis, is the simple answer. But there are no reliable ways of identifying who is at risk of anaphylaxis!
There is also a big problem with them not being used even when they are available.
Who needs one?
EAACI position paper – see Anaphylaxis management. Only a couple of absolute indications, otherwise a risk assessment.
Prescribing a pen is only part of the overall management: nothing worse than prescribing a pen and not properly discussing avoidance, or having a pen that does not get used when it should be, because it’s left at home or because no-one remembers how to use it or they are too scared to use it.
In various studies, prescribed AAIs were only used in a third of recurrent episodes, despite being available and in date in two-thirds of episodes. The reason(s) for non-use requires further study: parental questionnaires indicate that parents have a poor recall of anaphylactic symptoms and how to use the AAI despite training.
2021 Expert working group – MHRA set up after further coroner’s inquests into anaphylaxis deaths, following European safety review in 2015. Recommendations are:
Early adrenaline. Which means teaching families/children recognition of signs.
Need for 2 pens emphasized.
Brand specific training
Key messages on packaging eg “don’t delay”, “use second pen if necessary”
Posture detailed – “lie down with legs up”, “sit up if breathing difficult but don’t change position suddenly”, “stay lying down [regardless of whether you feel better or what people tell you to do]”
Wider availability of AAIs in public places likely to be beneficial but this would require legislative amendment as well as public training, and concerns about storage conditions and supply would need to be addressed.
Dosing errors in hospital common, but given pressure on AAI supply may not be great solution. Other solutions would be labelled kits, pre-filled syringes, different system of labelling adrenaline (!).
Reporting of device related adverse events, and anaphylaxis events (including re-establishment of fatal anaphylaxis registry).
Technique
Patient should lie down (but if respiratory symptoms then may be more comfortable sitting). Video available at Epipen and Jext websites. 3 minute training video with more explanation on Youtube. Or scan this:
Remove safety cap (Blue for Epipen, Yellow for Jext).
Jab orange (Epipen) or black (Jext) tip firmly into upper outer thigh, through clothing if necessary but avoid seams and pocket contents eg coins, mobiles – clicks as it activates.
Hold for 3 secs (Epipen), 10 secs (Jext).
Previous advice was to rub area (probably now white) vigorously for 10 seconds. Adrenaline causes vasoconstriction in skin, but vasodilatation in muscle so should be absorbed as long as IM. Not specified now.
Phone 999.
Dispose of device safely (device is self sheathing). Note that some drug left behind, which is normal, and that pen cannot be reused!).
Repeat after 5 minutes if necessary. Use a different leg!
Training checklist (from GOS):
When to use it
How to use it
When to carry it ie at all times!
Storage/disposal – should be protected from heat and light
Expiry date – reminder service available from support website (link above)
They come in two different doses – standard strength is 0.3 mg, there is a 0.15 mg strength prescribed for younger children (15-30kg). Emerade (not currently available) gcomes in a 0.5mg strength for adults and children over 12, which is a more appropriate dose for bigger people viz over 60kg.
If patient is under 15kg, CYANS guidance is that over 7.5kg, the potential benefit outweighs the risk. For those under 7.5kg, need to balance risk of anaphylaxis with risk of drug error from drawing up adrenaline from vial with syringe and needle.
Epipen has 18 month shelf life, self sheaths, and has a window to show ready to use. Blue safety cap, orange needle end. JEXT pen similarly self sheathing, coloured window to show whether it is live or not, 24 months shelf life. Yellow safety cap, black needle end. Same needle length.
Anapen has been discontinued. Had a shorter needle, different technique – remove caps from both ends, hold against leg, put your thumb over the end and press red button.
Emerade pen has safety cap over needle end – this is different from the other types but is logically simpler. Needle is 25mm long cf 15mm Epipen/Jext. Currently off market due to reliability of activation concerns.
Number of Pens
2018 MHRA review recommends 2 pens available at all times, and made the recommendation directly to families so they can demand them from their doctor! BSACI (2016) suggested children should in most cases just get 2 pens, 1 for home and 1 for school, but this was contradicted by later European Medicines Agency (EMA) and previous NICE guidance. Still not clear why they should ever by prescribed in single rather than twin packs…
due to uncertainties about the site of drug delivery and the speed of adrenaline action within the body, it is recommended that healthcare professionals prescribe 2 auto-injectors, which patients should carry at all times
the needle length of the device is now stated in the product information because this may be an important factor for the prescriber to consider when choosing a suitable auto-injector
the training of patients and their carers in the correct use of the product is important and manufacturers were required to update their educational materials
manufacturers should carry out studies in humans to more fully understand when and how much adrenaline reaches the blood stream, and how quickly and effectively it acts on body tissues when given through an auto-injector
EAACI guideline says number of pens should be guided by individual assessment, and BSACI also allow that 2 pens may be more appropriate in some cases, eg obesity, previous need for 2 doses, remoteness etc. There has been good evidence published indicating that one-third of children with anaphylaxis require a second dose of epinephrine (Kornblat P, et al Allergy Asthma Proc. 1999; 20: 383–6), and deaths have occurred despite a single injection, but most of these reports describe subcutaneous adrenaline use, rather than intramuscular use. Dose is more likely to be an issue with big teenagers (eg over 45kg).
If you carry your pen, know how and when to use it, then you are doing to do significantly better if you have a bad reaction than most other people, so don’t get too hung up on how many pens!
Spare pens in school
New legislation (2017) allows schools to obtain without prescription spare pens. These can be used if the pupil’s own pen is not immediately available or already given. Note that children with food allergies are not always prescribed adrenaline auto injectors but may still be at risk of anaphylaxis. The spare pen can be used in such children if:
The child’s care plan confirms child is at risk of anaphylaxis
A health care professional has authorised use of the spare pen in an emergency
The child’s parent/guardian has provided consent for a spare pen to be administered
Note that advice on using pens can be given over the phone by emergency services, if it is made clear pens are available.
Further information about spare adrenaline pens, and advice on reducing the risk of reaction sin school, treating reactions in school, staff training etc can be found at https://www.sparepensinschools.uk/
Needle length
Doing ultrasounds of thighs shows that in a significant proportion of people, including children under 5 with high BMI, the distance to muscle is more than 15mm (and not including any clothing). 82% of the obese children studied had skin surface to muscle depth greater than needle length. This was only true for 25% of the non-obese children. 3/4 the way down the thigh, only 17% of obese children and 2% of those not obese. Arkwright, Royal Manchester Children’s Hospital – 2013 Annual AAAAI meeting.
Some suggestion from injection models that “jet” of adrenaline penetrates significantly deeper than needle alone, that the angle, force used, whether the device is spring loaded or not, all potentially affect depth. So concerning, especially given the cases where multiple injections have failed to prevent death (eg Natasha Ednan-Laperouse).
Emerade had longer needle (25mm) but not currently available. So inject in lower lateral thigh?
2015 European medicine agency review discussed above concluded that training remains the paramount issue, although further research into needle length should be done.
2021 Review found that blood adrenaline levels actually higher after Epipen and Jext cf
Failure to use
In a 3 year Canadian study of 1500 ED episodes, almost 50% of adults were not treated with epinephrine in or outside of the hospital. Slightly better for kids, 28.7%. Almost all of these children had been prescribed auto-injectors. The need for multiple doses in ED was less in those who received epinephrine outside ED. [Allergy, Asthma & Clinical Immunology 2014, 10(Suppl 2):A3 doi:10.1186/1710-1492-10-S2-A3]
In a Canadian email survey of 1885 anaphylaxis survivors (adults and kids, food and insect etc), 73% did not give epipen. Most common reason for not giving, was that an antihistamine had been given first. Only 28% gave reason as being that they did not have epipen! 13% judged reaction as mild. 41% of epipens were given by someone other than patient, mostly family of children. 53% of epipen users had previously used one before. [simons, clark, camargo – JACI 2009:124;301 doi:10.1016/j.jaci.2009.03.050]
Failure to prescribe
In an online survey presenting 10 paediatric allergy case histories to paediatricians (all were severe, although only 1 case specifically mentioned anaphylaxis). There was significant variability in prescribing practices. Although all allergists and generalists prescribed an autoinjector (94.4% and 92.6%, respectively) or would offer the patient a choice about autoinjectors (5.6% and 7.4%, respectively) in the case specifically mentioning anaphylaxis, many cases had almost no consensus on prescription of adrenaline autoinjector. The prescribing patterns of allergists and generalists showed no significant differences for 9 of the cases. For the remaining case, which described a child with oral allergy syndrome, all specialists (n=54, 100%) reported that they would not prescribe an autoinjector (in line with guidelines) compared with only 20 (74.1%) of generalists (p<0.001). [Johnson MJ, Foote KD, Moyses HE et al. (2012) Practices in the prescription of adrenaline autoinjectors. Pediatric Allergy and Immunology 23: 124-7]
In a survey of all GPs in Scotland, 90% of the 613 respondents had prescribed adrenaline autoinjectors. However, only 49% of prescribers were confident in use of these devices, and only 17% had access to a trainer pen for demonstration to patients. If called upon in an anaphylactic emergency (experienced by 36% of respondents), only 50% of respondents would use the appropriate dose and 14% would use an inappropriate route of administration (subcutaneous or intravenous). [Lowe G, Kirkwood E, Harkness S (2010) Survey of anaphylaxis management by general practitioners in Scotland. Scottish Medical Journal 55:11-4]
Failure to Use – Doctors
When scenarios presented to junior doctors (same questions posed 10 years earlier) – all recognized need for adrenaline in anaphylaxis scenario but dose often wrong and 25% gave adrenaline IV. For non-anaphylactic scenarios, adrenaline frequently recommended eg inhaled peanut. Not much improvement over decade. [Postgrad Med J 2015;91:3-7 doi:10.1136/postgradmedj-2013-132181 ]
Editorial discusses how doctors know that adrenaline is required in anaphylaxis, but that this knowledge is often not translated into practice. Many of these doctors had had ALS training; most had not worked in an emergency department. Simulation? Australian experience. Booster sessions?
Management of anaphylaxis involves treating the acute emergency, in the community first (see adrenaline autoinjectors), then in hospital, and then arranging appropriate follow up. See also anaphylaxis definition.
Hospital
APLS guidelines (updated 2021) on management of acute anaphylaxis from the United Kingdom Resuscitation Council.
No distinction between anaphylactic and anaphylactoid reactions – confusing and may lead to inadequate treatment. Patients taking beta blockers may have a more severe reaction and respond less well to adrenaline.
Adrenaline is the only evidence based treatment specified in the guidelines. It is therefore the treatment of choice. You could argue that anaphylaxis is the one condition in which the ABC approach is not appropriate – as soon as anaphylaxis is suspected, you should give intramuscular adrenaline, and then proceed to airway, breathing etc.
Adrenaline is underused. 34% of cases of anaphylaxis in Patel’s metanalysis did not receive adrenaline (my calculation from table III); 10% needed more than 1 dose [Patel JACI 2021]. In scenario based studies, adrenaline is often not given.
Adrenaline by the intramuscular route is safe. If in doubt, just give it! Dose is 0.15mg for under 6yrs, 0.3mg for 6-12yrs, 0.5mg for over 12. This is slightly different from the adrenaline autoinjector dose the child may have been prescribed for home use.
Repeat within five minutes if there is no improvement or if the patient’s condition deteriorates – not based on any evidence!
New guideline does not mention steroids or antihistamines at all! But does include IV bolus with second dose IM adrenaline after 5 minutes .
Posture emphasised in new guidance – Lie down with legs raised, or allow sitting up in semi-recumbent position if that helps breathing. Beware sitting up, standing and walking even if feeling better – reported trigger for cardiac arrest – so caution when transferring.
Refractory Anaphylaxis
After that, if still not improving, there is a new Refractory anaphylaxis guideline.
Get expert help. Intravenous adrenaline should only be given by experienced practitioner.
Give repeated IM doses of adrenaline, or if experienced, start low dose IV adrenaline infusion:
1 mg (1 mL of 1 mg/mL [1:1000]) adrenaline in 100 mL of 0.9% sodium chloride, ie 1:100 000.
Beware BP cuffs and piggy back lines that will interfere and potentially cause extravasation.
Start at 0.5-1ml/kg/hr and titrate.
Use ECG monitoring.
Use nebulised adrenaline for stridor, neb salbutamol for wheeze or bronchospasm.
After that intubation, inhalational anaesthetics (good for bronchospasm), repeat fluid boluses.
Discharge
Before, advice was observe for 6-12 hours, or admit if child. Now this has been risk stratified, with 6-12 hour rule applying for most cases. Exceptions are:
2hr discharge if a) good response (5-10 minutes), to b) single dose adrenaline, c) given within 30 minsPLUS complete resolution PLUS already trained and with 2 unused AAIs PLUS adequate supervision
At least 12 hours after resolution if any of:
severe, needed more than 2 doses adrenaline
severe asthma, or had severe respiratory compromise
possibility of ongoing absorption eg slow release medication
late at night or potential to not respond to any deterioration
areas where emergency care difficult
or in context of supervised challenge
No reliable way to predict biphasic reaction so this should be discussed and decision made by senior clinician.
Basic principles are to not discharge too soon, in case of a biphasic attack, but just as importantly, to consider prevention of further episodes (which involves making a diagnosis), and giving the patient and their family the appropriate information and skills to deal with an unexpected further allergic reaction.
Who needs an Adrenaline auto-injector?
EAACI position paper suggests:
Absolute indications:
Previous cardiovascular or respiratory reaction to a food, insect sting or latex.
Child with food allergy and co-existent persistent asthma.
Relative indications:
Any reaction to small amounts of a food (e.g. airborne food allergen or contact only via skin).
History of only a previous mild reaction to peanut or a tree nut.
Remoteness of home from medical facilities.
Food allergic reaction in a teenager.
Prescribing a pen is only part of the overall management: nothing worse than prescribing a pen and not properly discussing avoidance, or having a pen that does not get used when it should be, because it’s left at home or because no-one remembers how to use it or they are too scared to use it.
Referral to an allergist is highlighted. According to a Mayo Clinic study, 35% of those referred by emergency department (ED) had an alteration in the diagnosis or suspected trigger after allergy/immunology follow up. Either anaphylaxis was ruled out; or an unknown trigger was successfully identified; or the suspected trigger was ruled out. Allergists are also good at identifying new triggers, different from the one suspected (JACI In Practice 2014)
How well is anaphylaxis managed by emergency departments?
In 1 study from Arkansas, n=187 patients (all under 19), food (44%) and stings (22%) were the main triggers, whereas 29% had no identifiable allergen. Only 47% (n = 87) received adrenaline in the ED and only 31% of those via the preferred IM route (the rest were treated subcutaneously). 61% received autoinjectors at discharge. Only 45% received an allergy referral. [Ped Emergency Care 2016] Similar results from Birmingham, Alabama in 2010.
Most cases of anaphylaxis are coded as “allergic reaction” rather than anaphylaxis, which suggests hospital statistics are likely to represent only a minority of the cases coming to hospital. In the study above, before the 2006 NIAID anaphylaxis guidelines, only 20% of cases were accurately coded.
Oral Ondansetron use for gastroenteritis has become v popular in many emergency departments. In 1 study of 18 EDs, where it was a standard in nearly half all cases, there was no overall improvement in rates of either intravenous rehydration (remained around 18%) or hospital admission. There was a small decrease in re-attendance rates.
There was also a wide variation between institutions: perhaps the problem is not using Ondansetron it correctly eg not giving it soon enough, or rushing into IV fluids before allowing the drug time to work
Same group looked at Ondansetron in diabetic children with vomiting, again, usage increased from 0 to 67%. Admission rates dropped from 62% to 49% between these eras, as did use of IV fluids, but Ondansetron had no independent benefit.
From Archimedes Blog. (Freedman S et al. JAMA Pediatr 2014;168:321–29, see also Editorial)( (Leung J et al. J Pediatr 2014. doi.org/10.1016/j.jpeds.2014.10.020). )
Children with congenital heart disease – Consider stopping domperidone therapy or discuss with parents/carers and ensure that cardiac monitoring is regularly performed. Consider offering an alternative treatment where appropriate.
Other children with established reflux or nausea and vomiting – Take no immediate action in patients already established on domperidone. Consider reducing the dose (where appropriate) to 250microgram/kg three times a day at the next convenient review. Consider routine cardiac monitoring where there are concerns (e.g. cardiovascular instability,
concomitant CYP3A4 inhibitors prescribed).
In new patients, always give a proper trial of feed thickeners before considering pharmacological intervention – at least two weeks. In more serious cases, and after the introduction of thickeners then consider the benefits and risks of medical anti-reflux/anti-acid secretion treatment.
If domperidone is to be used, give an initial maximum of
250micrograms/kg three times a day. Where reflux or nausea is refractory to
this then give increased doses to a maximum of 400micrograms/kg (max
20mg) three times a day and recommend regular cardiac monitoring.
Patient Information Leaflet entitled “Domperidone for gastrooesophageal
reflux” available from www.medicinesforchildren.org.uk
Oseltamivir and Zanamivir licensed for treatment and the former also for post-exposure prophylaxis.
Cochrane review 2014 found little evidence of benefit. But this was based on community studies in healthy populations.
“Use of neuraminidase inhibitors in influenza” [October 2015, Academy of Medical Sciences] indicates that the use of antivirals can be beneficial in certain situations, but of limited use in others. Additionally, a recent review “Expert opinion on neuraminidase inhibitors for the prevention and treatment of influenza – review of recent systematic reviews and meta-analyses” August 2017, European Centre for Disease] supports use as treatment and prophylaxis.
severe immunosuppression (includes prednisolone r≥2mg/kg/day for ≥1 week);
morbid obesity (Z score BMI 3.33 or higher).
Oseltamivir (Tamiflu) PO or NG is first line, unless severe immunosuppression and A(H1N1) variant prone to resistance dominant – then zanamavir.
Start treatment within 48hrs, do not wait on lab confirmation of diagnosis. May still be benefit in life threatening illness when started up to 5 days after onset. Rule is within 36hrs if child and zanamavir.
should NOT be used in otherwise healthy patients but can be considered if felt to be “at serious risk of developing complications”.
Test for resistance if no response after 5 days of treatment.
Presumes flu-like illness and circulating influenza, CMO publishes advice when surveillance levels cross threshold. Highly virulent strain would change things, of course. Further details including use of anti-virals at HPS.
Oseltamavir dose is twice daily for 5 days. Oral only, capsules can be opened and added to something sugary (very bitter). Liquid preparation available but limited supply, prioritise for infants. Give by NG if necessary. Licensed for treatment at all ages now, prophylaxis only over 1 yr. Diarrhoea and vomiting are the only significant side effects.
The earlier it is started the better: starting within 12 hours reduced duration of illness by 3 days, start within 48 hours and only 1 day benefit. 5% of childhood infections will become resistant whereas this is unusual in adults, probably due to kids having higher viral loads in primary infection. Consider resistance if no benefit after 5 days treatment.
Zanamivir used for adolescents 12 years and older – taken again twice daily for 5 days by diskhaler (age less important than ability to use device!). No resistance, very low rate of side effects (wheeze!). Zanamavir is preferred in severely immunocompromised AND (probable) A(H1N1)pdm09 disease, as resistance is higher . Unlicensed IV form of zanamavir is available on compassionate named patient basis.
For prophylaxis, vaccination best! But consider using anti-virals (NICE recommendations) for post-exposure prophylaxis with Oseltamivir where:
13yrs or older
Have a risk factor, as above
Influenza A or B is circulating, as above
Present within 48hrs of close contact exposure
Have not had flu vaccine for this season, or too recently for it to have been effective (within 14 days), or the wrong type, or have a condition that means vaccine may not be fully effective, or localised outbreak eg care home
Dose is once daily for 10 days. Treatment for up to 6 weeks might be required during an epidemic.
Other comments
Amantadine not recommended – targets M2 protein, only effective against type A influenza, rapid resistance and side effects common.
2 adolescents in Japan have committed suicide while on oseltamavir, plus there have been a number of other neuropsychiatric reports.
Peramivir is IV preparation with marketing authorization in EU, not yet available in UK.
Under-recognized, particularly when chronic blockage (without itch/sneezing) rather than sneeze/discharge. Late phase reactions involving Eosinphil induction by T cells tends to produce chronic swelling and non-specific irritability eg cold air. Nose problems impact with everything connected eg eyes, sinuses, middle ear, lungs. Differential is wide eg CF/PCD, deviated septum, polyps.
Considered trivial, and indeed work and school attendance not much affected but quality of work much more so – proven sleep problems, tiredness, impaired cognitive function. In a study of UK 15-17yr olds , students who dropped a grade between prelims and finals were significantly more likely to have had allergic rhinitis symptoms, to have taken antihistamines, and in particular, Piriton (OR=1.7). 43% increased odds of dropping an exam grade, goes up to 71% if using a sedating antihistamine [Samantha Walker, JACI 2007: 120; 381-387]
In asthma, prevalence of rhinitis increases over time to very high levels. If significant symptoms then OR=4 for poor asthma control (equivalent to poor inhaler technique!), plus combination of acute rhinitis and URTI gives OR=20 for asthma exacerbation.
Persistent defined as more than 4/7 per week, for more than 4/52. Mod/severe defined as any impairment of sleep or activity, else “troublesome symptoms” (BSACI includes seasonal or not, where you might be considering immunotherapy).
On examination (with auroscope), blue boggy wet mucosa, ?nasal crease.
SPT is pretty good at finding causes – depends how many you screen for, of course! In a US study, 65% of patients (mixed adults/children) had a positive: house dust mite (HDM) most commonly, else trees, weeds, moulds. Aspergillus and Penicillium are indoor moulds, Alternaria is outdoors. Cat allergens are commonly found in homes without cats! Nasal challenge can be done if neg SPT/IgE (Rondon, Curr Op Allerg Clin Imm 2010).
Children/adults same, just watch for doses/side effects.
Intranasal steroids most effective. Antihistamines, both intranasal and oral, are effective. Consider also leukotriene receptor antagonist (LRTA) eg montelukast (esp if co-existing asthma). Oral decongestants and steroids are also used short term sometimes.
For intermittent symptoms or mild persistent, no preferred treatment option – intranasal antihistamine, oral antihistamine, decongestant, LTRA, or combination. Nasal saline douches eg Sterimar have some evidence for efficacy, also nasal filters (not caught on yet!).
If co-existing conjunctivitis, prob best to go straight to nasal steroid, else add oral/topical antihistamine, or topical cromone, or saline.
Oral decongestant should only be used for max 10/7, can be useful diagnostically. Similarly oral steroids, if poor response or where diagnosis still unsure.
Cromoglycate (Rynacrom) has a role in young children but prob less effective than topical steroid or anthistamine, and at 4-6x a day, certainly less convenient.
Nasal ipratroprium recommended for rhinorrhoea.
Azelastine spray (Rhinolast) has been discontinued, so only nasal antihistamine is now the combination product Dymista (with flutic, from age 12). Not as good as steroid, doesn’t seem to have much effect on congestion (prob non-type 1 mechanism). Bad taste, irritation.
Montelukast licensed for rhinitis in asthmatics where resistant to other treatments, from age 15! ARIA recommend for over 6.
Intranasal steroids superior to top/systemic antihistamine, LRTA (even combinations). They also help eye symptoms, whereas nasal antihistamines don’t. Beclometasone (from age 6yr) and budesonide have relatively high bioavailability so better to use fluticasone (from age 4, furoate or propionate) or mometasone (from age 6), esp if other steroid use eg for asthma/eczema.Technique is often an issue – most gets sprayed or sniffed into back of throat!
Nasal spray Technique – (see video) Shake, head slightly forward, aim at ceiling (better to use opposite hand?), don’t sniff. Gargle and spit if taste unpleasant. Keep with toothbrush or other marker of habitual routine.
See also immunotherapy – some evidence that immunotherapy for rhinitis reduces risk of asthma!
