Finding 'Sanjivani', Daily! (Part-2) Blog Space/Finding 'Sanjivani', Daily! (Part-2)

No. This blog is not about any miracle drug or vaccine against SARS Co-V2 virus responsible for the

current deadly pandemic of COVID19. This is regarding the class of medications already invented & used

by millions of people across the globe daily - by force or by choice. They are inhaler medications or as

commonly called "Pump".

Let me briefly narrate the evolution of inhaler medicines.

Before the era of modern medicine, concept of drug delivery through inhalation route was mainly

through nose & mediated by vapors, leading to the term, "medicated vapors". It was only after 1850s,

the idea of generating 'aerosols' for the purpose of inhalation by breaking liquid gained momentum.

Few devices were designed which can be classified in to "Atomizers" which did the same without baffle

& "Nebulizers" which required baffle. (Modern Jet Nebulizer in image below)

In 1950s, with invention of Metered Dose Inhaler (MDI) & suitable formulations like salbutamol, the

management of airway diseases got revolutionized as the device become small, portable & handy.

Slowly, modifications came in & today we have numerous varieties of inhalers - pressurized MDIs,

Breath Actuated MDIs, MDI with Spacer, Dry Powder Inhaler(DPI) with different devices, Multidose DPIs,

Jet nebulizer, Mesh nebulizer etc, which all have their own pros & cons, requiring utmost caution in

prescribing to suitable person.

When we look back into the history of respiratory diseases other than tuberculosis - the decade of 1950

holds the greatest significance. Apart from the first MDI being invented, two more significant

developments happened. The primary aim of the inhaler medication at that time was "symptomatic

relief". However with discovery of "Timed Vital Capacity" which is commonly known as "Forced

Expiratory Volume in 1st Second or FEV1", put the edifice of further research for the efficiency of inhaler

molecule - the increase in FEV1 or holding the rate of decline in FEV1 - became the standard endpoints

in many clinical trials.

The third significant development was understanding of the "Obstructive Airway Diseases" evolved with

description of elements of 'Chronic Obstructive Pulmonary Disease or COPD" in CIBA guest symposium

in the year of 1959. Slowly the elements of Asthma, COPD & Bronchiectasis became more clear.

In conclusion, the understanding of airway diseases, its measurement of impact & the treatment - all got

revolutionized in this decade.

As mentioned earlier, symptomatic relief was the chief indication of inhaler medications at that time.

The molecules available were sympathomimatics – or relievers as we know them now, which manifests

an important phenomenon called "Tachyphylaxis", meaning rapid & short term development of drug

tolerance. Elaborating, if the person required 2 puffs to control the symptom, slowly over period of

some time, one will require more than that dose to control the symptoms & hence becomes "addicted"

- as the inhaler medication requires to be taken more frequently to control the symptom.

However, this is not the case with other class of molecules which are known as anti-cholinergics acting

as "bronchodilators to widen the narrowed airways" and inhaled corticosteroids acting as "anti-

inflammatory - to reduce inflammation on airways".

As the understanding in the diseases & their management evolved, inhaled corticosteroids became the

first line management to treat Asthma: known as 'controller' with aim to take 'relievers' as much less

time as possible: a defining criteria to assess asthma control. There was enough evidence to suggest the

shift, that in the year of 2019 - GINA made fundamental change in the recommendation that even in

intermittent asthma - "SABA only" (read reliever only') treatment got abandoned.

Symbolism: A Pulmonologist passes through lot of thought processes to choose an inhaler just like

Hanumam's struggle to fetch the herb. An optimized inhaler therapy reduces the symptom (particularly

of breathlessness) & risk of the disease - just as sanjivani cured army to conquer the evil.

Sanjivani: a miracle herb described in the ancient scripture of "Ramayana", was obtained by Hanumanji

after unprecedented struggle. Very few people know that the herb was actually "inhaled" leading to

restoration of the army lead by Lord Shri Ram to conquer the evil. This blog provides holistic information

of inhaler medications.

Part-2 of this blog series briefly narrates the historical aspect & evolution of inhaler medications.

Dr. Jaykumar Mehta

MBBS (Gold Medalist)

MD, DNB, MNAMS, PD Fellow (Pulmonology) Consultant Interventional Pulmonologist (Zydus Hospital,

Ahmedabad)