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Running nose and cough medicine: Diphenhydramine Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing

Diphenhydramine Oral: Uses, Side Effects, Interactions, Pictures, Warnings & Dosing


Diphenhydramine is an antihistamine used to relieve symptoms of allergy, hay fever, and the common cold. These symptoms include rash, itching, watery eyes, itchy eyes/nose/throat, cough, runny nose, and sneezing. It is also used to prevent and treat nausea, vomiting and dizziness caused by motion sickness. Diphenhydramine can also be used to help you relax and fall asleep.This medication works by blocking a certain natural substance (histamine) that your body makes during an allergic reaction. Its drying effects on such symptoms as watery eyes and runny nose are caused by blocking another natural substance made by your body (acetylcholine).Cough-and-cold products have not been shown to be safe or effective in children younger than 6 years. Do not use this product to treat cold symptoms in children younger than 6 years unless specifically directed by the doctor. Some products (such as long-acting tablets/capsules) are not recommended for use in children younger than 12 years. Ask your doctor or pharmacist for more details about using your product safely.These products do not cure or shorten the length of the common cold and may cause serious side effects. To decrease the risk for serious side effects, carefully follow all dosage directions. Do not use this product to make a child sleepy. Do not give other cough-and-cold medication that might contain the same or similar ingredients (see also Drug Interactions section). Ask the doctor or pharmacist about other ways to relieve cough and cold symptoms (such as drinking enough fluids, using a humidifier or saline nose drops/spray).

How to use Diphenhydramine Hcl

Follow all directions on the product package. If your doctor has prescribed this medication, take it as directed. If you have any questions, ask your doctor or pharmacist.

Take the tablet, capsule, or liquid form by mouth with or without food. Measure liquid forms of this medication using a special measuring device/spoon. Do not use a household spoon because you may not get the correct dose. If you have a single-dose form of this medication (such as a single-use whistle), you do not need to measure the dose.

The rapidly-dissolving tablet or strip should be allowed to dissolve on the tongue and then swallowed, with or without water. The chewable tablets should be chewed thoroughly before being swallowed.

The dosage is based on your age, medical condition, and response to treatment. There are many brands and forms of diphenhydramine available. Read the dosing instructions carefully for each product because the amount of diphenhydramine may be different between products. Do not increase your dose or take this medication more often than directed.

To prevent motion sickness, take your dose 30 minutes before starting activity such as travel. To help you sleep, take your dose about 30 minutes before bedtime. If you continue to have difficulty sleeping for longer than 2 weeks, contact your doctor.

Tell your doctor if your condition does not improve or if it worsens.

Side Effects

Drowsiness, dizziness, constipation, stomach upset, blurred vision, or dry mouth/nose/throat may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

To relieve dry mouth, suck (sugarless) hard candy or ice chips, chew (sugarless) gum, drink water, or use a saliva substitute.

If your doctor has directed you to use this medication, remember that your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: mental/mood changes (such as restlessness, confusion), difficulty urinating, fast/irregular heartbeat.

Get medical help right away if you have any very serious side effects, including: seizures.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US – Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada – Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.


Before taking diphenhydramine, tell your doctor or pharmacist if you are allergic to it; or to dimenhydrinate; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: breathing problems (such as asthma, emphysema), high pressure in the eye (glaucoma), heart problems, high blood pressure, liver disease, seizures, stomach/intestine problems (such as ulcers, blockage), overactive thyroid (hyperthyroidism), difficulty urinating (for example, due to enlarged prostate).

This drug may make you dizzy or drowsy or blur your vision. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness or clear vision until you can do it safely. Avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Liquid products, chewable tablets, or dissolving tablets/strips may contain sugar and/or aspartame. Liquid products may also contain alcohol. Caution is advised if you have diabetes, liver disease, phenylketonuria (PKU), or any other condition that requires you to limit/avoid these substances in your diet. Ask your doctor or pharmacist about using this product safely.

Children may be more sensitive to the side effects of this drug. This drug can often cause excitement in young children instead of drowsiness.

Older adults may be more sensitive to the side effects of this drug, especially drowsiness, dizziness, confusion, constipation, or trouble urinating. Drowsiness, dizziness, and confusion can increase the risk of falling.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

This drug passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.


Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor’s approval.

Some products that may interact with this drug include: antihistamines applied to the skin (such as diphenhydramine cream, ointment, spray).

Tell your doctor or pharmacist if you are taking other products that cause drowsiness such as opioid pain or cough relievers (such as codeine, hydrocodone), alcohol, marijuana (cannabis), drugs for sleep or anxiety (such as alprazolam, lorazepam, zolpidem), muscle relaxants (such as carisoprodol, cyclobenzaprine), or other antihistamines (such as cetirizine, chlorpheniramine).

Check the labels on all your medicines (such as allergy or cough-and-cold products) because they may contain ingredients that cause drowsiness. Ask your pharmacist about using those products safely.

This medication may interfere with certain laboratory tests (including allergy skin test), possibly causing false test results. Make sure laboratory personnel and all your doctors know you use this drug.

Does Diphenhydramine Hcl interact with other drugs you are taking?

Enter your medication into the WebMD interaction checker


If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. Symptoms of overdose may include: severe drowsiness, seizures, widened pupils. In children, mental/mood changes (such as restlessness, irritability, hallucinations) may occur before drowsiness.

Keep all medical and lab appointments.

If you miss a dose, take it as soon as you remember. If it is near the time of your next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from moisture and light. Do not store in the bathroom. Do not freeze liquid forms of this medication. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.


diphenhydramine 50 mg capsule

Color: pinkShape: oblongImprint: AP 21

This medicine is a pink, oblong, capsule imprinted with “AP” and “21”.

diphenhydramine 25 mg capsule

Color: pink,clearShape: oblongImprint: CPC 835

This medicine is a pink, oblong, capsule imprinted with “AP” and “21”.

diphenhydramine 50 mg capsule

Color: pinkShape: oblongImprint: E 649 E 649

This medicine is a pink, oblong, capsule imprinted with “AP” and “21”.

diphenhydramine 25 mg capsule

Color: pink,naturalShape: oblongImprint: logo 20

This medicine is a pink, oblong, capsule imprinted with “AP” and “21”.

diphenhydramine 50 mg capsule

Color: pinkShape: oblongImprint: CPC 836

This medicine is a pink, oblong, capsule imprinted with “AP” and “21”.

diphenhydramine 25 mg capsule

Color: pink,clearShape: oblongImprint: CPC 835

This medicine is a pink, oblong, capsule imprinted with “AP” and “21”.

diphenhydramine 25 mg tablet

Color: pinkShape: oblongImprint: 44-329

This medicine is a pink, oblong, capsule imprinted with “AP” and “21”.


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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.

Cold and Cough Medicines: MedlinePlus

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What are cold and cough medicines?

Cold and cough medicines can help relieve symptoms of a common cold. The symptoms of a cold can include a sore throat, stuffy or runny nose, sneezing, and coughing.

You don’t usually need to treat a cold or the cough that it causes. You can’t cure a cold, and antibiotics won’t help you get better. But sometimes the symptoms can keep you awake or cause a lot of discomfort. In that case, cold and cough medicines can sometimes be helpful.

What are the different types of cold and cough medicines?

There are lots of different cold and cough medicines, and they do different things:

  • Nasal decongestants – unclog a stuffy nose
  • Cough suppressants – quiet a cough
  • Expectorants – loosen mucus in your lungs so you can cough it up
  • Antihistamines – stop runny noses and sneezing
  • Pain relievers – ease fever, headaches, and minor aches and pains

What do I need to know about taking cold and cough medicines?

Before taking these medicines, read the labels and follow the instructions carefully. Many cold and cough medicines contain the same active ingredients. For example, some of them include pain relievers. If you are taking these medicines and are also taking a separate pain reliever, you could be getting a dangerous amount of the pain reliever.

Do not give cold or cough medicines to children under two, and don’t give aspirin to children.

What else can I do to feel better for a cold or cough?

If you decide that you don’t want to take cold and cough medicines, there are other ways to feel better:

  • Drink lots of fluids
  • Get plenty of rest
  • Use a cool mist humidifier
  • Use saline nose drops or sprays
  • Use nasal suctioning with a bulb syringe, which can be very helpful in children under a year old

Centers for Disease Control and Prevention

  • Cold Remedies: What Works, What Doesn’t, What Can’t Hurt

    (Mayo Foundation for Medical Education and Research)

    Also in Spanish

  • Cough Medicine: Understanding Your OTC Options

    (American Academy of Family Physicians)

    Also in Spanish

  • Decongestants: OTC Relief for Congestion

    (American Academy of Family Physicians)

    Also in Spanish

  • 5 Tips: Natural Products for the Flu and Colds: What Does the Science Say?

    (National Center for Complementary and Integrative Health)

  • Acetaminophen Level

    (National Library of Medicine)

    Also in Spanish

  • Don’t Double Up on Acetaminophen

    (Food and Drug Administration)

    Also in Spanish

  • High Blood Pressure and Cold Remedies: Which Are Safe?

    (Mayo Foundation for Medical Education and Research)

    Also in Spanish

  • Echinacea

    (National Center for Complementary and Integrative Health)

  • Echinacea: What Should I Know about It?

    (American Academy of Family Physicians)

    Also in Spanish

  • Zinc for Colds: The Final Word?

    (Mayo Foundation for Medical Education and Research)

    Also in Spanish

  • ClinicalTrials. gov: Antitussive Agents

    (National Institutes of Health)

  • ClinicalTrials.gov: Histamine Antagonists

    (National Institutes of Health)

  • Article: Antitussive efficacy of the current treatment protocol for refractory chronic cough:. ..

  • Article: Chiral analysis of dextromethorphan and levomethorphan in human hair by liquid…

  • Article: Benzonatate Exposure Trends and Adverse Events.

  • Cold and Cough Medicines — see more articles

  • Food and Drug Administration

  • Cough and Cold Medicine Abuse (For Parents)

    (Nemours Foundation)

    Also in Spanish

  • Coughs and Colds: Medicines or Home Remedies?

    (American Academy of Pediatrics)

    Also in Spanish

  • Daily Medicine Record for Your Child

    (Food and Drug Administration)

  • Should You Give Kids Medicine for Coughs and Colds?

    (Food and Drug Administration)

    Also in Spanish

what diseases are there, are snot and cough related

Published: June 09

Updated: December 30

Reading time: 4 minutes

Cough and runny nose are considered the most common symptoms of respiratory diseases. They can complicate life and significantly worsen the quality of life of the patient.

How a runny nose and cough are related

The simultaneous appearance of two symptoms in respiratory infections is caused by the peculiarities of the structure of the upper respiratory tract. The nasal cavity, throat, trachea and bronchi are interconnected, therefore, when viruses and bacteria enter, the inflammatory process quickly spreads from the upper sections to the lower ones. Cough can occur in parallel with a runny nose and be a manifestation of pharyngitis, laryngitis, bronchitis. If left untreated, a runny nose can be complicated by sinusitis, the flow of mucus down the back of the throat, causing coughing attacks.

Coughing may occur if the nose is blocked. The fact is that with a cold, a person has to breathe through his mouth. The constant passage of the air stream dries the mucous membrane, because of this, a sore throat is felt and a cough occurs.

The cause of cough in the common cold is mucus. It flows down the back wall of the pharynx and irritates the mucous membrane, because of which the patient begins to cough reflexively. In this case, a strong cough often manifests itself at night and prevents the patient from resting calmly.

The two symptoms are not always related. Cough without a runny nose accompanies chronic diseases of the upper respiratory tract, for example, pharyngitis. In this case, the cause of coughing will be a sluggish inflammation in the throat.

Symptoms of what diseases can be a runny nose and cough

During an illness, all the forces of the body are directed to fight the infection. Runny nose, sneezing, and coughing clear the airways of mucus that contains viruses, bacteria, and foreign substances. In addition, coughing is a reflex reaction that occurs in response to irritation of cough receptors located in the respiratory tract and excitation of the cough center of the brain. It helps to remove foreign bodies and irritants from the respiratory system.

There are several diseases that are characterized by a runny nose and cough:

  • laryngitis – an inflammatory process localized in the mucous membrane of the larynx, often accompanied by a runny nose and barking cough;
  • pharyngitis – a lesion of the mucous membrane of the pharynx, which is characterized by coughing and sore throat when swallowing;
  • tracheobronchitis and pneumonia – inflammation of the respiratory tract involving the lower respiratory tract, caused by viruses or bacteria.

Colds appear fever, weakness and headache . In the first days of illness, the cough is usually dry and unproductive, bringing the patient severe discomfort. Closer to recovery, sputum gradually begins to depart. Barking dry cough and runny nose in a child are characteristic of laryngitis, which in childhood can occur in the form of obstructive laryngitis (false croup).

Colds in children and adults are accompanied by an increase in body temperature. Coughing and a runny nose without fever can be symptoms of an allergy – in response to the ingestion of allergens, a sore throat, itching and redness of the eyes, discharge from the nose and coughing appear. Only a doctor can find out the exact cause of the ailment – he will conduct an examination, prescribe the necessary tests and make a diagnosis.

How to treat cough and runny nose

The main goal of treatment is to treat the cause of the disease. The patient is prescribed inhalations, physiotherapy, heavy drinking. To eliminate unpleasant symptoms, drugs from different groups are used.

  • Antipyretics. If the disease is accompanied by fever, non-steroidal anti-inflammatory drugs can be used – they relieve fever and facilitate general well-being.
  • Vasoconstrictor drugs. Drops in the nose with a runny nose help eliminate swelling of the mucous membrane and nasal congestion, so that the patient can breathe freely.
  • Antibiotics. Apply only in cases where a bacterial infection is confirmed.
  • Antihistamines. Allergy medicines are indicated for the relief of cough and runny nose caused by an allergic reaction and in case of an acute respiratory infection in a patient with allergies.
  • Cough preparations. The choice of medicine depends on the type of cough. With a wet productive cough with the separation of thick viscous sputum, it is necessary to stimulate and maintain its separation, and with a dry cough, conditions are created for the discharge of mucus. Use syrups, tablets, solutions for oral administration and use for inhalation through a nebulizer.

Rengalin can be used for both dry and wet coughs. The drug is available in two forms – in a solution for oral administration and in the form of lozenges. The active components of the drug help to fight dry, wet and residual cough, which does not go away for a long time. Rengalin is suitable for both adults and children over 3 years old. To exclude contraindications before taking the drug, you should consult with your doctor.

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Cough and runny nose | Doctor MOM®

Why can a runny nose be accompanied by a cough?
What diseases cause runny nose and cough?
How to treat cough and runny nose
When should I see a doctor?
Preparations Dr. MOM ® in the treatment of cough

Cough and runny nose are symptoms that are familiar to almost every person. This is one of the most common manifestations of diseases of the upper respiratory tract. But no matter how “familiar” these symptoms may be, each time they seriously complicate life and lead to a deterioration in overall well-being. And although cough and runny nose are not an independent diagnosis, but only signs of a disease, they need to be treated, as they can lead to a significant deterioration in the quality of life. For example, irritation and inflammation of the mucosa sometimes develop due to frequent and annoying coughing attacks membranes of the throat, a cough can permanently disrupt the appetite and quality of sleep, and with a prolonged runny nose, the nasal mucosa loses some important functions (for example, protective). This makes it important to timely and, most importantly, correct treatment of not only the underlying disease, but also its symptoms – cough and runny nose.

Why can a runny nose be accompanied by a cough?

Respiratory features . Cough caused by respiratory infections is often accompanied by a runny nose. This is due to the fact that the human airways (nasal cavity, oropharynx, nasopharynx, larynx, trachea, etc.) are closely related anatomically and functionally. Therefore, pathogens can easily spread from the upper respiratory tract to the lower ones, and an “innocent” runny nose, left without treatment, can quickly lead to diseases such as laryngitis, pharyngitis, bronchitis, etc. Mechanical causes . With a runny nose, discharge from the nose flows down the back wall of the nasopharynx, which irritates the mucous membrane and provokes a cough. Violation of nasal breathing . With nasal congestion, a person is forced to breathe through the mouth, which can cause drying of the throat mucosa, perspiration and cough. In some cases, cough and runny nose may be unrelated symptoms, but this does not eliminate the need for their treatment.

What diseases cause runny nose and cough?

How to treat cough and runny nose depends on what causes these symptoms and how long they have been observed. The underlying disease and the duration of its course affect the characteristics of cough (productive, unproductive, predominantly nocturnal, etc.) and runny nose (with nasal congestion, nasal breathing, watery or thick discharge, etc.). The most common causes of cough and runny nose are the following factors.

Diseases of the respiratory system:

Infectious diseases:

  • colds and influenza – most often seasonal diseases that occur in an acute form, they are caused by more than 300 varieties of viruses;
  • tuberculosis is a chronic disease caused by Koch’s bacillus and some other related microorganisms;
  • measles, rubella, scarlet fever are acute infectious diseases that mainly affect children.

In the acute course of the infectious process, cough and runny nose are accompanied by an increase in body temperature. But if the temperature remains within the normal range, this does not mean that there is no danger to health. This combination of symptoms such as cough, runny nose and normal temperature may indicate an allergy: nasal discharge and a scratchy throat that provokes coughing may be a reaction of the immune system to the presence of allergens. To relieve symptoms in such cases, TYZIN 9 can be used.0101 ® Allergy.

How to treat cough and runny nose

In order to properly treat cough and runny nose in adults and children, it is important to identify the cause of these symptoms. Therefore, it is imperative to contact a doctor who diagnoses the underlying disease and gives recommendations for therapy. What to do with a cough and runny nose depends on what provoked these symptoms. For their treatment, different groups of drugs can be prescribed.

Cough relievers . With a wet cough, it is important to maintain its productivity, as it removes infected sputum from the bronchi. With an unproductive (dry) cough, it is necessary to create conditions to facilitate the removal of sputum. Syrup Dr. MOM ® with “FITO BRONHO 10 formula” 3 and herbal cough lozenges Dr. MOM ® with “FITO BRONHO formula” 1 help to convert an unproductive (dry) cough into a productive one. The active ingredients in these products help to eliminate inflammation, which is the cause of coughing, as well as to more effectively remove sputum from the bronchi. Vasoconstrictors . They are prescribed for nasal congestion to eliminate swelling of the mucous membrane and restore nasal breathing. TIZIN ® Xylo BIO can be used not only to relieve nasal congestion, but also to restore and moisturize its mucous membrane. Antivirals . This group of drugs is prescribed in cases where the disease is caused by viral infections. Antipyretics . If a strong cough and runny nose are accompanied by high fever, it is reasonable to use drugs that normalize it, for example, RINZA 9 tablets0101® . Antihistamines . This group of drugs can be used to treat allergic cough and runny nose. Vitamins and minerals . Depending on the composition of the complex, they can have a different effect: from strengthening the body’s defenses to improving the absorption of nutrients. Doctor MOM ® Phyto ointment can be used as a topical preparation. The essential oils included in its composition have an inhalation effect 4 when applied to the wings of the nose, thus helping to restore nasal breathing. In combination with vegetable lozenges and syrup Dr. MOM ® ointment eliminates the main symptoms of the disease.

When should I see a doctor?

The symptoms themselves (cough and runny nose) are reason enough to see a doctor. However, there are a number of symptoms that accompany a runny nose and cough, in which you need to see a doctor as soon as possible. These include:

  • high body temperature that cannot be reduced by conventional antipyretics;
  • acute pain in ears, throat;
  • difficulty breathing, difficulty swallowing;
  • loss of voice or severe hoarseness;
  • coughing up an excessive amount of sputum, detecting traces of pus, blood in it;
  • acute pain in the chest and/or back during severe coughing.