Drug Uses

Periactin is used to treat sneezing; runny nose; itching, watery eyes; hives; rashes; itching; and other symptoms of allergies and the common cold.
Although not approved by the FDA for this purpose, Periactin has been used to stimulate appetite in underweight patients.
Periactin may also be used for purposes other than those listed in this medication guide.

How to use

Take Periactin exactly as directed by your doctor. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.
Take each dose with a full glass of water.
Periactin can be taken with or without food.
To ensure that you get a correct dose, measure the syrup form of Periactin with a special dose-measuring spoon or cup, not with a regular tablespoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one.
Never take more of this medication than is prescribed for you. The maximum amount of Periactin that you should take in 1 day is 32 mg.
Drug Class and Mechanism

Periactin is an antihistamine. Periactin blocks the effects of the naturally occurring chemical histamine in your body.

Missed Dose

Take the missed dose as soon as you remember. However, if it is almost time for your next dose, skip the missed dose and take only your next regularly scheduled dose. Do not take a double dose of this medication unless otherwise directed by your doctor.

Storage

Store Periactin at room temperature away from moisture and heat.

Warnings/Precautions

Do not take Periactin if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A very dangerous drug interaction could occur, leading to serious side effects. Before taking this medication, tell your doctor if you have

glaucoma or increased pressure in the eye;
a stomach ulcer;
an enlarged prostate, bladder problems, or difficulty urinating;
an overactive thyroid (hyperthyroidism);
hypertension or any type of heart problems; or
asthma.
You may not be able to take cyproheptadine, or you may require a lower dose or special monitoring during treatment if you have any of the conditions listed above.

Possible Side Effects

Stop taking Periactin and seek emergency medical attention if you experience an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives).

Other, less serious side effects may be more likely to occur. Continue to take Periactin and talk to your doctor if you experience:

sleepiness, fatigue, or dizziness;
headache;
dry mouth; or
difficulty urinating or an enlarged prostate.
More Information

Periactin is to be used only by the patient for whom it is prescribed. Do not share it with other people.
If your symptoms do not improve or if they become worse, check with your doctor.