Which is better, ointment, cream, gel, spray or aerosol. Differences in dosage forms for external use.

Ointment, gel, cream, spray, aerosol. Differences between dosage forms for external use

Often, when we come to the pharmacy to buy a particular medicine, we are faced with the problem of choice - a very large assortment of medicines.
To treat just one disease, the pharmacist will offer you several medication options. They will be from different manufacturers, with different active ingredients, and in different release forms. So try not to get confused here and make the right choice. It’s also good if you first went to your doctor and received recommendations or a prescription for the medicine. Well, if not, you’ll have to figure it out yourself or rely on the help of a pharmacy employee. In case of skin problems, be it allergies, irritation, burns, wounds or something else, we often use topical medications in therapy. The forms of release of these drugs are quite varied. The most common are ointment, gel, cream, spray and aerosol. In our article we will try to understand which form of medication will be effective in a given case. All medications for external use contain an active ingredient and a base. The basis of the drug determines its release form - liquid, solid, gaseous, soft, etc. Well, the form itself determines the action and properties of the drug - absorption, speed of action, duration of effect and much more.

Choosing sunscreens

Ultraviolet spectra UVA, UVB

Before we choose between cream, spray or lotion, a few words about what specific rays you should seek protection from, because this is important.

Ultraviolet, which reaches us through the ozone layer, consists of two spectra: UVA and UVB.

UVA rays are long waves, 95% of all ultraviolet radiation that reaches us. The most dangerous rays because they penetrate clouds, clouds, glass and, of course, skin. They act painlessly and invisibly. They can provoke skin changes, accumulate and at one moment spill out in the form of a sharp loss of skin quality, wrinkles, dryness and sagging, and malignant formations.

UVB rays provoke the production of melanin in the skin, which is essentially a protective reaction of the skin to ultraviolet irritants. And it is these rays that, when exposed to the skin for a long time, cause sunburn.
UVC rays are the most dangerous, but, fortunately, they are blocked by the ozone layer and do not reach the ground.

When choosing a sunscreen
, pay attention to the mark about the spectrum from which the cosmetics are stated to be protected. The best rating for you will be UVA+UVB or UVA/UVB or UV-Protect, which means that you will be protected from both types of dangerous radiation.

Sun filters

Another important thing in choosing products from the active sun (this is not when it is very hot, but when UV rays are very active. Information about sun activity can even be in weather forecasts) are filters or screens. Some of them are considered natural; natural filters are called physical filters, while others are of chemical origin. Let's look at it in order to understand what exactly you should look for on the bottles.

Physical filters:

Reflective. This filter “works” on the surface of the skin. They are good because they are not absorbed, but this is the downside - they don’t last well if you combine tanning and swimming. Such creams should be applied every 2-3 hours. Creams with physical filters contain mineral pigments titanium dioxide or zinc oxide. May leave white marks on the skin. Considered the safest.

Chemical filters:

Light absorbing. These are synthesized substances that react with ultraviolet radiation, provide a high degree of protection and, turning into an absorber of UV rays, prevent them from penetrating the skin. In such creams, look for cinnamates, salicylates, and benzophenones. Light-absorbing filters Unlike physical filters, chemical filters are waterproof and do not leave whitish stains on the body. But still, chemistry is chemistry, so before applying the cream, make sure that it does not cause allergies - test it on a small area of the body.

SPF index in cosmetics

Choosing sunscreen

, pay attention to the SPF index, which means the degree of solar protection. The lower the index, for example SPF 10, SPF 15 and 20, the lower the barrier against radiation will be. Such creams are suitable for skin care not only in summer, but all year round, especially in spring, when the skin is weaned from the intensity of the sun. However, this does not mean that this cream is worse. The minimum index is 5, and the maximum that can be found on the shelves is 100.

For intense summer sun exposure, we recommend staying in the middle - choose an SPF value from 25 to 50. The remaining numbers can sometimes turn out to be a marketing ploy by the manufacturer and the degree of their protection will be a little more than 2-5% of the average indices. When choosing an index, be guided by your skin phototype. The lighter the natural shade, the higher the SPF.

Ointments for external use

In this dosage form, the main components are the active substance and a fat base (vegetable oils, petroleum jelly, lanolin and others). The ointment is used for application to dry, tight surfaces, skin with peeling, and dry rashes. Recommended for use in the treatment of chronic inflammation. Can be applied to scars and seals. In addition to the therapeutic effect, the ointment moisturizes and softens the affected area. Due to the content of a large amount of fat, the active component acts longer and penetrates into the damaged surface as deeply as possible. If you apply the ointment to a bandage and place it on the affected area of the body, its effectiveness will increase. It is not recommended to apply ointment to weeping rashes or open wounds.

Pros and cons of using ointments

The disadvantages include the fact that the ointment easily stains clothes, which can then be difficult to wash off greasy stains. The ointment is not completely absorbed into the skin, so after a while, you will need to remove its remnants from the skin yourself. The shelf life of ointments, as a rule, is long - the fat base does not allow the substance to dry out quickly. At the same time, be sure to follow the storage conditions; some ointments are stored at a certain temperature in the refrigerator. The downside is that the fatty base penetrates over time even through a tightly closed tube lid, so the ointments must be stored in a separate additional package.

TESTS

Depending on the dosage form, quality control of aerosols and sprays includes assessing the pressure in the package, the tightness of the package, checking the valve, determining the percentage of yield of the package contents, the average dose weight, the number of doses in the package, dosage uniformity, and mass uniformity. For non-inhalation aerosols and sprays containing a suspension of active substances, the particle size is determined; for inhalation aerosols, the respirable fraction is determined.

For aerosols and sprays, which are emulsions and suspensions, separation is allowed during storage, but they must be easily re-emulsified and resuspended when shaken to ensure uniform distribution of the active substance in the drug.

Aerosols intended for inhalation must comply with the General Pharmacopoeia Monograph “Dosage forms for inhalation.”

Packing pressure

Pressure measurements are carried out only for aerosols in which the propellants are compressed gases.

The packages are kept at room temperature for 1 hour and the pressure inside the package is measured with a pressure gauge (accuracy class 2.5), which must comply with the requirements of the pharmacopoeial monograph or regulatory documentation, but should not exceed 0.8 MPa (8 kgf/cm2).

Packaging tightness (for aerosols)

Method 1. An aerosol can without a cap and a spray or nozzle is completely immersed in a water bath at a temperature of (45 ± 5) °C for no less than 15 minutes and no more than 30 minutes for a glass can and no less than 10 minutes and no more than 20 minutes for metal. The thickness of the water layer above the valve stem must be at least 1 cm. There should be no release of gas bubbles.

Method 2. Select 12 previously unused aerosol packages. Each package without a cap and a sprayer or nozzle is weighed to the nearest 0.001 g (m0) and left in an upright position at room temperature for at least 3 days. The aerosol package is then weighed again to the nearest 0.001 g (m1).

Record the duration of the test in hours (T).

Release the aerosol package from its contents in accordance with the method specified in the pharmacopoeial monograph or regulatory documentation. Weigh the empty packaging with an accuracy of 0.001 g (m2), calculate the average mass of the contents with an accuracy of 0.001 g (m3) using the formula:

Where

n is the number of aerosol packages tested.

Calculate the leakage rate of the contents of the package in grams per year (Vm) using the formula:

Calculate the rate of leakage of the contents of the package per year as a percentage of the average weight (V%) using the formula:

Unless otherwise specified in the pharmacopoeial monograph or regulatory documentation, the average annual leakage rate for 12 packages should not exceed 3.5% of the average weight of the contents of the package and for no one package should exceed 5.0%. If at least one package has a leak rate greater than 5.0% per year, but no package exceeds 7.0%, a leak test is performed on an additional 24 packages. No more than 2 packages out of 36 may have a leak rate greater than 5.0% and none of them may have a leak rate greater than 7.0% per year.

If the contents of the package are less than 15 g, the average leakage rate for 12 packages must not exceed 525 mg/year and for no single package must exceed 750 mg/year. If for at least one package the leak rate exceeds 750 mg/year (but not more than 1.1 g/year), then a leak test is carried out on another 24 packages. No more than 2 packages of 36 may have a leak rate greater than 750 mg/year and no package of 36 may have a leak rate greater than 1.1 g/year.

Output of package contents

The test is carried out for non-dosed aerosols and sprays. The package is weighed together with the sprayer or nozzle with an accuracy of 0.01 g (m4). By pressing the sprayer or nozzle, remove all contents from the package and weigh the package again along with the sprayer or nozzle with an accuracy of 0.01 g (m5).

The percentage yield (X) is calculated using the formula:

where m6 is the mass of the contents indicated on the label, g (or obtained by multiplying the nominal volume by the density of the drug).

Unless otherwise specified in the pharmacopoeial monograph or regulatory documentation, the percentage yield of the contents of the package must be at least 90%, and the result is considered the arithmetic average obtained when determining the percentage yield of the contents of 3 packages.

Dose mass uniformity

The test is carried out for metered aerosols and sprays containing solutions. The test for inhalation aerosols is carried out in accordance with the General Pharmacopoeia Monograph “Dosage forms for inhalation” (test “Uniformity of the delivered dose”).

Monitoring of this indicator should be carried out not only for doses released from one package, but also for doses received from different packages. The dose selection procedure should include the selection of doses at the beginning, in the middle and at the end of use of the drug.

Release one dose and discard it. After at least 5 s, shake the package for 5 s, release and discard one dose again. Repeat this procedure 3 more times, unless otherwise indicated in the pharmacopoeial monograph or regulatory documentation. Weigh the packaging. Shake the package for 5 seconds, release and discard one dose, and weigh the package again. The mass of the released dose is calculated from the difference.

The test is repeated for another 9 doses specified in the pharmacopoeial monograph or regulatory documentation. The average dose weight and deviations of individual values from the average dose weight are calculated.

The medicinal product is considered to have passed the test if no more than 1 out of 10 individual masses deviates from the average mass by an amount exceeding 25%, with no more than 35%. If 2 or 3 results fall outside the 75 - 125% range, the test is repeated with 20 other doses. No more than 3 out of 30 values may be outside the range of 75 to 125%, and all values must be within the range of 65 to 135%.

Number of doses per package

The test is carried out for metered aerosols and sprays.

Method 1. Release the contents of one package, releasing doses at intervals of at least 5 seconds. The number of doses released is recorded.

It is permissible to carry out the test simultaneously with the determination of dosage uniformity.

Method 2. The package is weighed together with the sprayer or nozzle with an accuracy of 0.01 g (m2). By pressing the sprayer or nozzle, release all the contents from the package and weigh the package again along with the sprayer or nozzle with an accuracy of 0.01 g (m5).

The average number of doses (nav) in one package is calculated using the formula:

where mav is the average mass of one dose, g.

The number of doses obtained as a result of the test must be no less than that indicated on the label.

Particle size

The test is carried out for non-inhalation aerosols and sprays containing a suspension of active substances. Determination methods and requirements for particle size must be specified in the pharmacopoeial monograph or regulatory documentation.

Respirable fraction

The test is carried out for inhalation aerosols in accordance with the General Pharmacopoeia Monograph “Aerodynamic distribution of fine particles”.

Dosing uniformity

The test is carried out for metered aerosols and sprays containing emulsions or suspensions. The test for inhalation aerosols is carried out in accordance with the General Pharmacopoeia Monograph “Dosage forms for inhalation”.

The test is carried out using an apparatus or installation capable of quantitatively retaining the dose released from the nebulization device. Shake the package for 5 seconds, release and discard one dose. After at least 5 s, shake the package again for 5 s, release and discard one dose. Repeat this procedure 3 more times, unless otherwise indicated in the pharmacopoeial monograph or regulatory documentation. After 5 s, one dose is released into the receiver of the device. The contents of the receiver are collected by successive washes and the content of the active substance in the combined wash waters is determined.

The test is repeated for another 9 doses specified in the pharmacopoeial monograph or regulatory documentation.

A drug passes the test if 9 out of 10 results are between 75 and 125% of the mean and all results are between 65 and 135%. If 2 or 3 results fall outside the 75 - 125% range, the test is repeated with 20 other doses. No more than 3 out of 30 values may be outside the range of 75 to 125%, and all values must be within the range of 65 to 135%.

For aerosols and sprays containing multiple active substances, a dosage uniformity test must be performed for each substance.

PACKAGE

In accordance with the requirements of the General Pharmacopoeia Monograph “Dosage Forms”.

MARKING

In accordance with the requirements of the General Pharmacopoeia Monograph “Dosage Forms”. The labeling of aerosols must contain warnings: “Keep away from the heating system and direct sunlight”, “Do not open”, “Protect from falls and impacts” and others if necessary.

STORAGE

In accordance with the requirements of the General Pharmacopoeia Monograph “Storage of Medicines”. In packaging that ensures stability during the specified shelf life of the medicinal product, in a place protected from light at a temperature of 8 to 15 ° C, unless otherwise indicated in the pharmacopoeial monograph or regulatory documentation.

Download in PDF OFS.1.4.1.0002.15 Aerosols and sprays

Gels for external use

Unlike ointment, the gel does not contain fats or oils at all. This is a viscous transparent or translucent substance containing water as a base, active ingredient and thickeners. The gel is best used to treat weeping skin wounds - it will have a drying effect and, by forming an invisible film on the surface, will protect the skin from the penetration of bacteria. It can also be applied to suppuration, or to a surface that secretes a small amount of blood. The gel, due to its structure, is evenly distributed, quickly absorbed and dries, and does not clog pores. If it is better to apply the ointment at night, avoiding contact with clothing, then the gel can be used at any time of the day, it adheres well to the skin and almost does not stain clothes.

Bibliography

Lee, Laurie A., et al. " Growth velocity reduced with once-daily fluticasone furoate nasal spray in prepubescent children with perennial allergic rhinitis
"The Journal of Allergy and Clinical Immunology: In Practice 2.4 (2014): 421-427.
Mehuys, Els, et al. " Self-medication in persistent rhinitis: overuse of decongestants in half of the patients
"The Journal of Allergy and Clinical Immunology: In Practice 2.3 (2014): 313-319.
Mortuaire, G., et al. " Rebound congestion and rhinitis medicamentosa: nasal decongestants in clinical practice. Critical review of the literature by a medical panel
» European annals of otorhinolaryngology, head and neck diseases 130.3 (2013): 137-144.
Read also: Steam cleaner for bedbugs - reviews and instructions for use

Did you like the news? Follow us on Facebook

Nasal sprays serve as an effective alternative to conventional nasal drops. It is more convenient to use drugs in the form of sprays than drops. And, unlike in the form of tablets and syrups, aerosols act locally, allowing you to get rid of it much faster.

What is a runny nose? With a viral disease, the volume of mucus produced sharply increases, which is why nasal congestion occurs. When using a vasoconstrictor spray, swelling decreases, and then the airways are cleared of accumulated mucus.

Creams for external use

This type of medicine is made on the basis of oil and water, in a ratio of approximately 50 to 50 percent. It is well absorbed into the skin, but the active substance penetrates shallowly. It is not recommended to be applied to open wounds, but it is optimal for treating weeping lesions, skin with blisters with liquid contents, flaking surfaces, skin with swelling, and itching. The cream is used to treat acute inflammation. It relieves swelling and dries the affected areas of the skin. The cream, like the gel, can be applied to the skin during the day and not be afraid that some of the substance will remain on clothing - after application, within a few minutes, it will be completely absorbed.

Aerosols for nasal congestion in the absence of a runny nose

If it is difficult or even impossible to breathe through your nose, but no discharge is observed from it, then you can choose any of the sprays listed below. These drugs effectively affect adrenaline receptors in the nasal passages and, by constricting blood vessels, relieve swelling. These sprays have an unpleasant feature: if you do not follow the time intervals specified in the instructions between their use and use the medicine more often than necessary, then the effect of using the aerosol will last less and less time. To avoid this, you need to strictly follow the recommendations for the drug and do not constantly spray the spray into your nose.

For nasal congestion (list of aerosols):

1. "Otrivin".

Excellent spray imported from Switzerland. Has a powerful and long-lasting vasoconstrictor effect. Contains substances that moisturize the mucous membrane, which softens the irritating effect on it. The composition contains eucalyptus and menthol, which cool inflamed tissues and make breathing easier.

2. “Lazolvan rino”.

A spray for nasal congestion, which, like the previous drug, contains eucalyptus with menthol, the refreshing effect of which is also enhanced by camphor. Swelling in the nose is relieved quickly with this remedy and the effect lasts a long time.

An effective preparation containing salts of the Adriatic Sea. Moisturizes the mucous membrane, cleanses the nose of dust and germs.

3. "Aqua Maris Strong."

The effect of this spray is similar to that of strong vasoconstrictor aerosols, but without the side effects inherent in the latter; perfectly relieves swelling and makes breathing easy and free.

Medicine in the form of spray and aerosol

Spray and aerosol are popular dosage forms on the pharmaceutical market, which are often confused by the common man.
They are intended for treating various wounds, skin, mucous membranes, nasopharynx, and burns with the drug. They are also used for inhalation. The characteristics and appearance of the spray and aerosol are quite similar. But the main difference between them will be the principle of drug delivery to the body and the volume of the substance supplied. In a spray, the medicine is supplied by pressing the piston of a mechanical pump, and spraying from it occurs in doses. Well, in an aerosol, the drug is supplied due to excess pressure inside the cylinder after opening the valve. The bottles in both cases are sealed, due to which the medicine remains sterile; neither air nor any external irritants get inside. The spray supplies larger particles of the active substance (more than 5 microns), the aerosol sprays small particles (1-5 microns). Due to their microscopic size, the particles of the active substance easily penetrate the site of application, thereby providing a quick therapeutic effect. Another advantage of these dosage forms is that when treating the medication there is no direct contact with the wounded surface, which means there is no risk of infection during application.

Most often, medicines for the treatment of runny nose, diseases of the oral cavity and larynx, and antiviral drugs are produced in the form of a spray. Anti-burn medications and drugs for the treatment of bronchial asthma are often produced in aerosol form.

What is the difference between a spray and an aerosol?

How to distinguish a spray from an aerosol?
Just recently you learned why the same drug exists in different forms of release. Separately, we looked at drugs for internal use: tablets, capsules, powders, syrups, and so on (using the example of Ambrobene and Nurofen).

Medicines for external (local) use are also found in a variety of forms. For example, in pharmacy windows you will find ointments, drops, sprays and aerosols for the common cold.

Aerosol and spray are two seemingly identical, but at the same time, completely different forms of release.

Aerosols and sprays are used for inhalation, intranasal (through the nose) or sublingual (under the tongue). They are also applied to the skin, wounds and mucous membranes.

How are spray and aerosol similar?

Both dosage forms are finely dispersed systems. What does it mean? The smallest particles of a solid or liquid substance (dispersed phase) are suspended in a gaseous (dispersed) medium, usually in the air.
Stable atomization of drug microparticles. From the primary packaging (bottle or cylinder), the medicine is dosed in portions or supplied continuously.
After each use, the packaging remains sealed. The medicine is protected from air and contaminants from the outside, as it does not come into contact with the external environment.

What is the fundamental difference between a spray and an aerosol?

Even experts confuse dosage forms. Let's figure it out.

The characteristics of the spray and aerosol are similar. However, when choosing a release form, their significant differences should be taken into account. We are talking about the method of delivering the drug and the size of the sprayed particles.

And now more specifically.

Aerosol

Dosage form aerosol

Primary packaging is a cylinder.
The drug is delivered by opening the valve.
At the moment of spraying, excess pressure is created inside the cylinder.
Aerosols can be continuous or metered (see spray).
Spray small particles (2-5 microns).

Examples of drugs: anti-burn (Panthenol, Olazol), for the throat (Hexoral, Ingalipt, Kameton).

Some medications come in both forms: aerosol and spray.

Spray

Dosage form spray

Primary packaging is a polymer bottle.
The drug is delivered by pressing the plunger of a micropump (small mechanical pump).
In this case, the pressure in the bottle and the pressure outside it are the same (the pressure in the bottle is equal to atmospheric pressure).
After spraying, the piston moves to its original position. In this case, the cavity from which the medicine is squeezed out is filled with a new portion. That is, the action is dosed. This mechanism serves as a liquid seal and prevents air from entering the bottle.
Sprays larger particles (more than 5 microns).

Examples of drugs: for the nose (Tizin, Vibrocil), for the throat (Lugol, Hexasprey, Tantum Verde).

Do not spray or aerosol!

Dosing according to the “syringe” principle

Some medications are mistakenly considered to be sprays. Primary packaging is a polymer bottle with a sprayer. However, these release forms differ from the spray:

The medicine is administered through a small hole by squeezing the bottle (the “syringe” principle).
In this case, an uncontrolled release of liquid from the bottle occurs.
The nature of the spray depends on the force and duration of pressing on the bottle, as well as its position. If you ignore the vertical position, the product will not be sprayed, but supplied as a stream.
After the first use, the seal of the bottle is broken.

Examples of drugs for the nose: Nazivin, Nazol, Dlynos.

Drops

Liquid dosage form dosed in drops

As for small children, drugs for the common cold are selected for them taking into account age restrictions. The spray and aerosol are very atomized, and the child may choke. Therefore, for babies there is another form of release - drops.

How to spray a particular dosage form correctly - read the instructions. Carefully read the dosing rules, as well as storage features and the recommended period of use after opening.

Would you like to see similar articles in your feed? Subscribe and Like!

Treat consciously!

Your #CaringPharmacist

Even more in the Telegram channel: t.me/lekarstvo_zdorovie

Source: https://zen.yandex.ru/media/lekarstvo_zdorovie/chem-otlichaetsia-sprei-ot-aerozolia-5a69a51adcaf8e1790630314

If in doubt, consult your doctor

Each medicine and its release form is good “to the point”. Not every person will be able to easily choose the medicine and the dosage form that will be most effective, and, what is equally important, will not cause harm due to improper use. Our advice is to always strictly follow the recommendations of your doctor and do not self-medicate. If you can’t get an appointment with a specialist, you can listen to the advice of a pharmacist at a pharmacy - a person with a medical education who will help you make the right choice.