Do not use phenylephrine if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction leading to serious side effects could occur.
Before using this medication, tell your doctor if you have
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high blood pressure;
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heart disease, hardening of the arteries, or irregular heartbeats;
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thyroid problems;
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diabetes;
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glaucoma or increased pressure in the eye(s);
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an enlarged prostate or difficulty urinating;
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liver disease; or
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kidney disease.
You may not be able to use phenylephrine, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.
Phenylephrine is in the FDA pregnancy category C. This means that it is not known whether it will harm an unborn baby. Do not use this medication without first talking to your doctor if you are pregnant.
Phenylephrine may pass into breast milk and affect a nursing baby. Do not use this medication without first talking to your doctor if you are breast-feeding a baby.
If you are over 60 years of age, you may be more likely to experience side effects from phenylephrine. You may require a lower dose of this medication.
Use phenylephrine exactly as directed by your doctor, or follow the instructions that accompany the package. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.
Take each oral dose with a full glass of water.
Your doctor or healthcare professional will administer injectable phenylephrine.
Do not use more of this medication than is recommended on the package or by your doctor. Too much medication could be harmful
If your symptoms are accompanied by a high fever, or if they do not improve in 7 days, see your doctor.
Store phenylephrine at room temperature away from moisture and heat.
Use the missed dose as soon as you remember. However, if it is almost time for the next
dose, skip the dose you missed and use only the next regularly scheduled dose.
If you experience any of the following serious side effects, stop using phenylephrine and seek emergency medical attention or contact your doctor immediately:
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an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives);
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seizures;
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unusual behavior or hallucinations; or
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an irregular or fast heartbeat.
Other, less serious side effects may be more likely to occur. Continue to take phenylephrine and talk to your doctor if you experience
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dizziness, lightheadedness, or drowsiness;
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headache;
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insomnia;
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anxiety;
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tremor (shaking) or restlessness;
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nausea or vomiting; or
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sweating.
Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or especially bothersome.
Do not take phenylephrine for longer than 7 days if the condition does not improve or if the symptoms are accompanied by a high fever.
Do not use more of this medication than is recommended on the package or by your doctor. Too much medication could be harmful
Use caution when driving, operating machinery, or performing other hazardous activities. Phenylephrine may cause dizziness, drowsiness, or impaired concentration. If you experience dizziness, drowsiness, or impaired concentration, avoid these activities.
Do not use more of this medication than is recommended on the package or by your doctor. Too much medication could be harmful
Use caution when driving, operating machinery, or performing other hazardous activities. Phenylephrine may cause dizziness, drowsiness, or impaired concentration. If you experience dizziness, drowsiness, or impaired concentration, avoid these activities.
Do not use phenylephrine if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction leading to serious side effects could occur.
Before taking phenylephrine, tell your doctor if you are taking any other medicines especially any of the following:
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medicine to treat high blood pressure or a heart condition;
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medicine to treat diabetes;
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weight loss medication;
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another decongestant (cold or allergy product); or
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a tricyclic antidepressants such as amitriptyline (Elavil, Endep), doxepin (Sinequan), amoxapine (Asendin), clomipramine (Anafranil), desipramine (Norpramin), imipramine (Tofranil), protriptyline (Vivactil), trimipramine (Surmontil), or nortriptyline (Pamelor).
You may not be able to take phenylephrine, or you may require a dosage adjustment or special monitoring during treatment if you are taking any of the medicines listed above.
Drugs other than those listed here may also interact with phenylephrine. Talk to your doctor or pharmacist before taking any prescription or over-the-counter medicines, including herbal products.
Seek emergency medical attention.
Symptoms of a phenylephrine overdose include extreme tiredness, sweating, dizziness, a slow heartbeat, and coma.
