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Sinus one side: Five Signs You Might have a Sinus Infection

Five Signs You Might have a Sinus Infection

12|07|2018

Sinusitis is an often-misused term. It is frequently, but incorrectly, used to refer to a similar, but distinct condition called rhinitis.  Rhinitis is inflammation of the nasal passages (not the sinuses), usually by a virus (the “common cold”) or an allergen (“hay fever”).  Sinusitis, on the other hand, is inflammation of the sinus cavities, which are behind the cheeks and forehead, not in the nose at all.  But, each of the sinuses drains through tiny “passages” into the nose.  Therefore, both conditions cause nasal discharge, leading to the confusion between them.  To add to the confusion, sinusitis often follows rhinitis.  Similar to rhinitis, sinusitis may also be cause by a virus or allergen but additionally, can be caused by bacteria or fungi.

Since antibiotics are almost never helpful with the much more common rhinitis, but are often indicated for sinusitis, it is important to distinguish the two conditions.   So, how does one know the difference?  Below are five signs of a sinus infection or sinusitis:

  • Headaches

Pain is among the most significant signs of sinusitis and is not common with rhinitis. There are sinuses located behind the forehead (frontal sinuses), behind the cheeks (maxillary sinuses), behind the nose (ethmoid sinuses), and near the eyes (sphenoid sinuses).  When any of these develops an infection, the resulting swelling and inflammation usually produces pain similar to a headache.

Pain may be felt generally throughout the head but will more often be experienced in the specific part of the head with the infected sinus.  Therefore, one sided, or very localized pain is more suggestive of a sinus infection that global head pain. Sinus headaches are often worse upon awakening in the morning due to the fluids that accumulated throughout the night. Changes in air pressure can also worsen sinus headaches.

The nasal drainage of rhinitis is usually thinner, clear or slightly yellow in color and expressed from both nostrils equally.   In contrast, the nasal drainage associated with a sinus infection is thicker, darker green or brown, and sometimes bloody.  Importantly, since sinus infections are most often one-sided, dark or bloody secretions from only one nostril strongly suggest a sinus infection rather than a cold.

  • Fever

More often than the common cold, sinusitis can cause an increase in your body temperature over 100.4 degrees Fahrenheit, the point at which temperature elevation is considered to represent a fever. You can relieve the fever and some of the discomfort by using over-the-counter medication such as Ibuprofen (Advil) and acetaminophen (Tylenol). As with all over-the-counter medications, you should consult your doctor prior to taking them. Children under three months of age who exhibit signs of sinusitis or fever should see a doctor right away.

Unlike the common cold, that tends to produce symptoms in multiple locations including the nose, the throat, the bronchi and the lungs, sinus infections are much more specific to the sinus that is infected.   Therefore, phlegm production from the lungs, loss of voice, intestinal symptoms, chest pain or trouble breathing all suggest conditions other than a sinus infection. Chest pain, trouble breathing, or bloody phlegm produced from a cough should prompt evaluation by a doctor right away

In the same way that many colds are inappropriately referred to as a sinus infection, sinus infections can be inappropriately confused with an unusually persistent cold. It is unusual for the common cold to last beyond 10-14 days.  Instead, since sinusitis often follows the common cold, cold-like symptoms that persist beyond 2 weeks often represent sinusitis.  In fact, acute sinusitis can last for four weeks while chronic sinusitis can last for months.  Therefore, any symptoms consistent with a cold or sinusitis that persist beyond two weeks should be evaluated for possible sinusitis.

If you have symptoms of a sinus infection, see your doctor or visit one of CapRock Health’s facilities.

Category: sinusitis

Sinus Pain or Congestion

Is this your child’s symptom?

  • Fullness, pressure or pain on the face over a sinus
  • Sinus pain occurs above the eyebrow, behind the eye, and under the cheekbone
  • Other common symptoms can be a blocked nose, nasal discharge, or postnasal drip

Symptoms

  • Most often, the pain or pressure is just on one side of the face.
  • Swelling around just one eye.
  • Other common symptoms are a stuffy or blocked nose or nasal discharge. Your child may also have a nasal drip down the back of the throat. This is called a postnasal drip.
  • Less common symptoms are bad breath or mouth breathing. Also, may have a sore throat and throat clearing from postnasal drip.
  • Age Limit. Sinus pain is not a common symptom before 5 years of age.

Causes of Sinus Congestion

  • Viral Sinus Infection. Part of the common cold. A cold infects the lining of the nose. It also involves the lining of all the sinuses.
  • Bacterial Sinus Infection. A problem when the sinus becomes infected with bacteria. (Occurs in 5% of colds). It starts as a viral sinus infection. Main symptoms are increased sinus pain or return of fever. The skin around the eyelids or cheeks may become red or swollen. Thick nasal secretions that last over 14 days may point to a sinus infection. This can occur in younger children.
  • Allergic Sinus Reaction. Sinus congestion often occurs with nasal allergies (such as from pollen). Sneezing, itchy nose and clear nasal discharge point to this cause.

Treatment of Sinus Congestion

  • Viral Sinus Infection. Nasal washes with saline. Antibiotics are not helpful.
  • Bacterial Sinus Infection. Antibiotics by mouth.
  • Allergic Sinus Reaction. Treatment of the nasal allergy with allergy medicines also often helps the sinus symptoms.
  • All Thick Nasal Drainage. Nasal secretions need treatment with nasal saline when they block the nose. Also, treat if they make breathing through the nose hard. If breathing is noisy, it may mean the dried mucus is farther back. Nasal saline rinses can remove it.

Color of Nasal Discharge with Colds

  • The nasal discharge changes color during different stages of a cold. This is normal.
  • It starts as a clear discharge and later becomes cloudy.
  • Sometimes it becomes yellow or green colored for a few days. This is still normal.
  • Colored discharge is common after sleep, with allergy medicines or with low humidity. Reason: all of these events decrease the amount of normal nasal secretions.

Bacterial Sinus Infections: When to Suspect

  • Yellow or green nasal discharge is seen with both viral and bacterial sinus infections. Suspect a bacterial infection if the discharge becomes thick (like pus). But, it also needs one or more of these symptoms:
  • Sinus Pain, not just normal sinus congestion. Pain occurs mainly behind the cheekbone or eye or
  • Swelling or redness of the skin over any sinus or
  • Fever lasts more than 3 days or
  • Fever returns after it’s been gone for over 24 hours or
  • Nasal discharge and post-nasal drip lasts over 14 days without improvement

When to Call for Sinus Pain or Congestion

Call 911 Now

  • Not moving or too weak to stand
  • Severe trouble breathing (struggling for each breath, can barely speak or cry)
  • You think your child has a life-threatening emergency

Call Doctor or Seek Care Now

  • Trouble breathing, but not severe. Exception: gone after cleaning out the nose.
  • Redness or swelling on the cheek, forehead or around the eye
  • Severe headache and getting worse
  • Severe pain and not better after using care advice
  • Weak immune system. Examples are: sickle cell disease, HIV, cancer, organ transplant, taking oral steroids.
  • Fever over 104° F (40° C)
  • Your child looks or acts very sick
  • You think your child needs to be seen, and the problem is urgent

Contact Doctor Within 24 Hours

  • Headache lasts more than 48 hours
  • Fever lasts more than 3 days
  • Fever returns after being gone more than 24 hours
  • Earache occurs
  • Sinus pain (not just pressure) and fever
  • You think your child needs to be seen, but the problem is not urgent

Contact Doctor During Office Hours

  • Sinus pain (not just pressure or fullness) lasts more than 24 hours, after using nasal washes
  • Thick yellow or green pus draining from nose and not improved by nasal washes. Exception: yellow or green tinged secretions are normal.
  • Sinus congestion and fullness lasts more than 14 days
  • Nasal discharge lasts more than 2 weeks
  • You have other questions or concerns

Self Care at Home

  • Normal sinus congestion as part of a cold

Seattle Children’s Urgent Care Locations

If your child’s illness or injury is life-threatening, call 911.






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Care Advice for Sinus Congestion

  1. What You Should Know About Sinus Congestion:
    • Sinus congestion is a normal part of a cold.
    • Nasal discharge normally changes color during different stages of a cold. It starts as clear, then cloudy, turns yellow-green tinged, then dries up.
    • Yellow or green-tinged discharge. This is more common with sleep, antihistamines or low humidity. (Reason: decrease the amount of normal nasal secretions.)
    • Usually, nasal washes can prevent a bacterial sinus infection.
    • Antibiotics are not helpful for the sinus congestion that occurs with colds.
    • Here is some care advice that should help.
  2. Nasal Saline to Open a Blocked Nose:
    • Use saline (salt water) nose spray (such as store brand). This helps to loosen up the dried mucus. If you don’t have saline, you can use a few drops of water. Use bottled water, distilled water or boiled tap water. Teens can just splash a little water in the nose and then blow.
    • Step 1: Put 3 drops in each nostril.
    • Step 2: Blow each nostril out while closing off the other nostril. Then, do the other side.
    • Step 3: Repeat nose drops and blowing until the discharge is clear.
    • How often: Do saline rinses when your child can’t breathe through the nose.
    • Saline nose drops or spray can be bought in any drugstore. No prescription is needed.
    • Reason for nose drops: Suction or blowing alone can’t remove dried or sticky mucus.
    • Other option: use a warm shower to loosen mucus. Breathe in the moist air, then blow each nostril.
  3. Fluids – Offer More:
    • Try to get your child to drink lots of fluids.
    • Goal: Keep your child well hydrated.
    • It also will thin out the mucus discharge from the nose.
    • It also loosens up any phlegm in the lungs. Then it’s easier to cough up.
  4. Humidifier:
    • If the air in your home is dry, use a humidifier. Reason: Dry air makes nasal mucus thicker.
  5. Decongestant Nose Spray (Age 12 years or Older):
    • Use this only if the sinus still seems blocked up after nasal washes. Use the long-acting type (such as Afrin).
    • Dose: 1 spray on each side. Do this 2 times per day.
    • Always clean out the nose with saline before using.
    • Use for 1 day. After that, use only for symptoms.
    • Don’t use for more than 3 days. (Reason: Can cause rebound congestion).
    • Decongestants given by mouth (such as Sudafed) are another choice. They can also open a stuffy nose and ears. Side effects: They may make a person feel nervous or dizzy. Follow the package directions.
  6. Pain Medicine:
    • To help with the pain, give an acetaminophen product (such as Tylenol).
    • Another choice is an ibuprofen product (such as Advil).
    • Use as needed.
    • Try saline first. Sometimes it alone relieves the pain.
  7. Cold Pack for Pain:
    • For pain or swelling, use a cold pack. You can also use ice wrapped in a wet cloth.
    • Put it over the sinus for 20 minutes.
    • Caution: Avoid frostbite.
  8. Allergy Medicine:
    • If the child also has nasal allergies, give an allergy medicine.
    • Long-acting allergy medicines (such as Zyrtec) are best. Reason: these meds do not cause your child to act sleepy. Age limit: 2 and older.
    • A single dose of Benadryl can be given for any breakthrough symptoms.
    • No prescription is needed. Age limit: 1 and older.
  9. What to Expect:
    • With this advice, the viral sinus blockage goes away in 7 to 14 days.
    • The main problem is a sinus infection from bacteria. This can occur if bacteria multiply within the blocked sinus. This leads to a fever and increased pain. It needs antibiotics. Once on treatment, the symptoms will improve in a few days.
  10. Return to School:
    • Sinus infections cannot be spread to others.
    • Your child can return to school after the fever is gone. Your child should feel well enough to join in normal activities.
  11. Call Your Doctor If:
    • Sinus pain lasts more than 24 hours after starting treatment
    • Sinus congestion lasts more than 2 weeks
    • Fever lasts more than 3 days
    • You think your child needs to be seen
    • Your child becomes worse

And remember, contact your doctor if your child develops any of the ‘Call Your Doctor’ symptoms.

Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.

Last Reviewed: 07/17/2023

Last Revised: 12/30/2022

Copyright 2000-2023. Schmitt Pediatric Guidelines LLC.

Sine theorem. Formulas and Proofs

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Railroad tracks are parallel to each other, and trees grow at an angle to the ground. Alas, with the ratio of the sides in a triangle, everything is not so simple: to determine them, you need the sine theorem.

Proof of the sine theorem

The sine theorem is as follows: the sides of a triangle are proportional to the sines of the opposite angles.

Draw a standard triangle and write the theorem with the formula:

Formula of the sine theorem:

Prove the theorem using the triangle area formula in terms of the sine of its angle.

From this formula we get two ratios:

  1. On b we reduce, we use the rule of proportion and get:

From these two relations we get:

The sine theorem for the triangle is proved.

This theorem is useful to find:

  • The sides of a triangle given two angles and one side.

  • Angles of a triangle, given two sides and one included angle.

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Proof of the corollary of the sine theorem

The sine theorem has an important consequence. Let’s draw a triangle, describe a circle around it and consider the consequence through the radius.

, where R is the radius of the circle circumscribed about the triangle.

This is how three formulas for the radius of the circumscribed circle were formed:

The main meaning of the corollary of the sine theorem lies in this formula:

The doubled radius of the circumscribed circle is equal to the ratio of the side of the triangle to the sine of the opposite angle.

To prove the corollary of the sine theorem, consider three cases.

1. The angle ∠A = α is acute in triangle ABC.

Draw diameter BA 1 . In this case, point A and point A 1 lie in the same half-plane from the line BC.

Using the inscribed angle theorem, we see that ∠А = ∠А 1 = α. The triangle BA 1 C is right-angled, in it ∠ BCA 1 = 90°, since it rests on the diameter BA 1 .

To find leg a in triangle BA 1 C, multiply the hypotenuse BA 1 by the sine of the opposite angle.

BA 1 = 2R, where R is the radius of the circle

Therefore:

For an acute triangle with a circumscribed circle, the theorem is proved.

2. The angle ∠A = α is obtuse in triangle ABC.

Draw the diameter of the circle BA 1 . Points A and A 1 on opposite sides of the straight line BC. Quadrilateral ACA 1 B is inscribed in a circle, and its main property is that the sum of opposite angles is 180°.

Therefore, ∠А 1 = 180° – α.

Recall the property of a quadrilateral inscribed in a circle:

It is also known that sin(180° – α) = sinα.

In triangle BCA 1 , the vertex angle C is 90° because it rests on the diameter. Therefore, we find the leg and in this way:

α \u003d 2R sin (180 ° – α) \u003d 2R sinα

Therefore:

For an obtuse triangle with a circumscribed circle, the theorem is proved.

Commonly used obtuse corners:

3. Angle ∠A = 90°.

In rectangle ABC, angle A is right, and the opposite side is BC = α = 2R, where R is the radius of the circumscribed circle.

Therefore:

For a right triangle with a circumscribed circle, the theorem is proved.

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Examples of problem solving

The sine theorem and its consequences are actively used in problem solving. Let’s look at a few examples to reinforce the material.

Example 1. In triangle ABC ∠A = 45°, ∠C = 15°, BC = 4√6. Find AC.

How to solve:

  • According to the triangle sum of angles theorem:

    ∠A + ∠B + ∠C = 180°

    ∠B = 180° – 45° – 15° = 120°

  • Find the AC side using the sine theorem:

Answer: AC = 12.

Example 2. The hypotenuse and one of the legs of a right triangle are 10 and 8 cm, respectively. Find the angle opposite the given leg.

How we solve:

Let’s take the unknown angle as x. Then the aspect ratio looks like this:

Therefore:

So .

Answer: The angle is approximately 53.1°.

Memorize

The usual theorem: The sides of a triangle are proportional to the sines of the opposite angles.

Extended theorem: in an arbitrary triangle, the following relation holds:

, where R is the radius of the circumscribed circle around the triangle.

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  • The theorem of cosines and sines of a triangle. Formulas and examples

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    Grade 9 is a time full of new knowledge. In order not to get confused in the geometry theory, we recommend making cards with information on each topic. In this article you will find the most important thing about the cosine theorem.

    Formulation and proof of the cosine theorem

    First, let’s recall the Pythagorean theorem: in a right triangle, the square of the hypotenuse is equal to the sum of the squares of the legs.

    Formula Pythagoras :

    a 2 > + b 2 > = c 2 >, where a, b are legs, c is the hypotenuse.

    The cosine theorem reads as follows: the square of a side of a triangle is equal to the sum of the squares of its other two sides minus twice the product of these sides by the cosine of the angle between them.

    Cosine formula:

    a 2 = b 2 + c 2 – 2bc cos α

    In proof of the cosine theorem we use the formula for the length of a segment in coordinates. Consider this formula:

    BC 2 = (x 2 – x 1 ) 2 + (y 2 – y 1 ) 2

    In the proof of the BC cosine theorem is the side of the triangle ABC, which is denoted by the letter a. We introduce a convenient coordinate system and find the coordinates of the points we need. Point B has coordinates (c; 0).
    Coordinates of point С — (b cos α; b sin α) for α ∈ (0° ; 180°).

    cos 2 α + sin 2 α = 1 basic trigonometric identity.

    BC 2 = a 2 = (b cos α – c) 2 + b 2 sin 2 α = b 2 cos 2 α + b 2 sin 2 α – 2bc cos α + c 2 = b 2 (cos 2 α + sin 2 α) – 2bc cos α + c 2

    What was required to be proved.

    Tip: to get to grips with a complex topic faster, sign up for
    online courses in mathematics for children and teenagers.

    Using the law of cosines, you can find the cosine of the angle of a triangle:

    • 0285 > 0, the angle α will be acute.
    • When b 2 + c 2 – a 2 = 0, angle α will be right.
    • When b 2 + c 2 – a 2 < 0, the angle α will be obtuse.

    Memorize

    When the angle α is straight, then the cosine theorem turns into the Pythagorean theorem.

    Let’s formulate another proof of the cosine theorem .

    Let us be given a triangle ABC in which height CD is lowered from vertex C to side AB. This means:

    • AD = b × cos α,
    • DB = c – b × cos α.

    Write the Pythagorean theorem for two right triangles ADC and BDC:

    • h 2 = b 2 – (b × cos α) 2
    • h 2 = a 2 – (c – b × cos α) 2

    Equate the right sides of the equations:

    • b 2 – (b × cos α) 2 = a 2 – (c – b × cos α) 2 9003 2

    or

    • a 2 = b 2 + c 2 – 2bc × cos α

    If one of the corners at the base is obtuse (the height rests on the continuation of the base), it is completely similar to that considered above.

    Define sides b and c:

    • b 2 = a 2 + c 2 – 2ac × cos β;
    • c 2 = a 2 + b 2 – 2ab × cos γ.

    Solve your math homework for 5.

    Detailed solutions will help you understand the most difficult topic.

    Statement of the theorem for each side of the triangle

    The cosine theorem is valid for all sides of the triangle, i.e.: a

    b 2 = c 2 + a 2 – 2ca cos β s γ

    The cosine theorem can be used for any kind of triangle .

    Cosines of the angles of a triangle

    The cosine theorem allows you to find both the cosine and the angle of a triangle. Let’s find the cosines of the angles:

    Similarly:

    Determination of the angle using the cosine

    And now let’s pay attention to the angles.

    As we already know, the cosine of an angle from the interval (0°; 180°) determines the angle (as opposed to its sine).

    Let us be given a unit semicircle. If we are given cos α, then we are given a point on the upper semicircle and an angle α is given. Therefore, cos α uniquely determines the point M(cos α; sin α), and the angle ∠AOM is uniquely determined.

    Consideration of the limits of variation of cos α and sin α

    Consider the limits of variation of sine and cosine α. Recall that if α is the angle of a triangle, then it lies between 0° and 180°.

    Limit of cosine change: -1 < cos α < 1.

    Limit of change of sine: 0 < sin α ≤ 1.

    • If cos α > 0, then α ∈ ( 0°;90° )
    • If cos α < 0, then α ∈ (90°;180°)
    • If cos α = 0, then α = 90°

    Examples of solving problems

    Using the cosine theorem, you can solve geometry problems. Let’s consider some interesting cases.

    Example 1. Triangle ABC is given. Find the length CM.

    ∠C = 90°, AB = 9, BC = 3, AM/MB = 1/2, where M is a point on the hypotenuse of AB.

    How do we decide:

    1. Since AM + MB = 9, and AM / MB = 1/2, then AM = 3, MB = 6.
      From the triangle ABC we find cos B:

    2. From the triangle CMB by the cosine theorem we find the SM:

    Answer: CM = .

    Example 2. Given a triangle ABC, in which a 2 + b 2 < c 2 . Prove that ∠C is an obtuse angle.

    How to prove:

    1. Since a 2 + b 2 < c 2 , then cos C < 0, hence ∠C is obtuse.