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Phenylephrine related Questions

What is Phenylephrine?

Phenylephrine is commonly used to provide temporary relief from sinus, stuffy nose and ear problems caused from the common cold, flu, and allergies. This drug can help reduce the swelling in the nose and ears and makes it easier for someone to breathe. Phenylephrine can have various side effects such as mild stomach problems, difficulty sleeping, lightheadedness, dizziness, headache, etc. In some cases, it can even reduce the flow of blood to the hands and feet and in return making them cold. Those who use phenylephrine may have questions about this medication and its use.

Given below are some of the important questions about this drug that have been answered by different Experts.

What is the recommended dosage of phenylephrine for adults?

The normal dosage of phenylephrine for adults is 10 to 20 mg (milligrams) of liquid or tablets to be taken once every 4 hours as required. The dosage may differ depending on what form of the medication is being taken. The recommended dosage of the drug in its various forms is given below:
• Phenylephrine 7.5 mg/5 ml oral liquid – 15 mg taken orally every 6 hours. The dosage should not exceed 60 mg per day.
• Phenylephrine 10 mg oral tablet – 10 mg to be taken every 4 to 6 hours. A maximum of 4 doses to be taken everyday
• Phenylephrine 10 mg oral disintegrating strip – 10 mg to be taken orally every 4 hours
• Phenylephrine 10 mg/5 ml oral suspension, extended release – 10 to 20 mg to be taken orally every 12 hours
• Phenylephrine tannate 10 mg oral tablet, chewable, extended release – 10 to 20 mg to be taken orally every 12 hours
• Phenylephrine tannate 7.5 mg/5 ml oral suspension, extended release – 7.5 to 15 mg to be taken orally every 12 hours

What are the symptoms of phenylephrine overdose?

Some of the symptoms of Phenylephrine overdose include restlessness or nervousness, severe dizziness, sweating, vomiting, hallucinations, increased heart rate, fainting, seizures and weak or shallow breathing.

Is it safe to take phenylephrine and Mucinex together?

The main components in Mucinex are guaifenesin and pseudo ephedrine. Pseudoephedrine and phenylephrine, when taken together can increase the heart rate and blood pressure. Therefore, some doctors will recommend not taking these two nasal decongestants together.

Can phenylephrine be used to treat sickle cell trait?

Phenylephrine solution at the dose of 1 ml (milliliter) diluted with normal saline to a concentration of 100 to 500 micrograms/milliliter can be injected every 3 to 5 minutes for about an hour to treat sickle cell trait. If required, the dosage of the medication can be increased.

Does phenylephrine contain alcohol in it?

Though phenylephrine does not contain EtOH or alcohol, therefore it can be used in combination with alcohol.

What is the difference between pseudonephrine and phenylephrine?

The main difference between the decongestants pseudonephrine and phenylephrine are the chemical compounds that they are made of. While phenylephrine is normally used as a decongestant in a nasal spray, Pseudoephedrine is taken orally.

Can phenylephrine HCL be taken along with Flonase?

There are no known drug interactions between Flonase and phenylephrine HCL (hydrochloride) and hence these two medications can be taken together. The nasal spray will help increase the effectiveness of the Flonase by reducing mucus.

Is it safe for a 4 1/2 week pregnant woman to take phenylephrine?

The FDA (Food and Drug Administration) has categorized phenylephrine as a category C drug during pregnancy. Though it has been tested on animals and been proved to be harmful, there are no human studies to prove this. Hence, though there is a small risk of harm to the baby, the pregnant woman can consult her OB/GYN and take the medication.

Does phenylephrine nasal spray increase the heart rate?

The phenylephrine nasal spray can be absorbed systematically from the numerous tiny blood vessels in the nose and increase a person’s heart rate. The heart rate will come back to normal once the drug leaves the system.

Though phenylephrine is a fairly safe drug, there are certain precautions that need to be taken before using it. Individuals should inform their doctor if they are allergic to this medication as well as their medical history. Individuals should keep in mind that they do not drive or operate any heavy machinery when taking this medication as it is known to cause dizziness and lightheadedness. Individuals should speak to an Expert and get any questions that they may have about Phenylephrine answered.
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