How to use
Viagra Professional (Sildenafil Citrate) should be taken about 20 minutes before sexual intercourse. Take it only as directed, usually once a day. To achieve optimal results, Viagra Professional (Sildenafil Citrate) should be chewed, not swallowed. This allows for a faster absorption into the bloodstream. By swallowing this drug instead of chewing it, the results will be similar to those of traditional Viagra. If you take Viagra Professional after a fatty meal the medication may have little to no effect.

Overdose
If you suspect an overdose of Viagra Professional (Sildenafil Citrate), contact your local poison control center or emergency room immediately. Symptoms of an overdose may include severe dizziness, fainting or a prolonged erection. 

Missed dose
Viagra Professional (Sildenafil Citrate) is only taken when needed, so you are not likely to miss a dose.

Notes
Do not share this medication with others, since they may have a problem that is not effectively treated by this drug. Use of Viagra Professional (Sildenafil Citrate) does not protect against sexually transmitted diseases (e.g. HIV, Hepatitis B, gonorrhea, syphilis).

Storage
Store at room temperature between 59 and 86 degrees F (15-30 degrees C) away from light and moisture. KEEP THIS AND ALL MEDICATIONS OUT OF REACH OF CHILDREN.  

Important note
The above information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed that the taking of this medication is safe, appropriate or effective for you.

Precautions
Before using Viagra Professional (Sildenafil Citrate), tell your doctor your medical history, including:

• Allergies (especially drug allergies)
• Penis conditions such as fibrosis/scarring (e.g., Peyronie's disease)
• History of painful/prolonged erection (priapism)
• Sickle cell anemia
• Blood system cancers (such as leukemia or myeloma)
• Eye problems (retina diseases)
• Kidney or liver diseases
• Bleeding disorders
• Active stomach ulcers
• Heart diseases
• Stroke
• Very high or low blood pressure

Limit alcohol intake, as it may aggravate side effects of Viagra Professional (Sildenafil Citrate). Since Viagra Professional (Sildenafil Citrate) may cause dizziness, caution is advised when performing tasks requiring alertness (e.g., driving). To avoid dizziness and lightheadedness when rising from a seated or lying position, get up slowly. Women or children should not use Viagra Professional (Sildenafil Citrate). Elderly people may be more sensitive to the side effects of this drug, therefore caution is advised when Viagra Professional (Sildenafil Citrate) is used by this group.

Drug interactions

You should not take Viagra Professional (Sildenafil Citrate) if you are currently on a nitrate drug for heart problems or chest pains. Nitrates include:

• Nitroglycerin (common names Nitrolingual, Nitro-Bid, Nitro-Dur, Nitrostat Minitran, Deponit, Transderm-Nitro, and others)
• Isosorbide mononitrate (common names Monoket, Imdur, ISMO)
• Isosorbide dinitrate (Isordil, Sorbitrate, Dilatrate-SR)

This also includes nitrates that are found in various recreational drugs such as nitrite or amyl nitrate ('poppers'). Using Viagra Professional (Sildenafil Citrate) in conjunction with any of the above-listed medications may cause a drop in blood pressure, which can result in dizziness, fainting, a stroke or, in extreme cases, a heart attack.

Before you start taking Viagra Professional (Sildenafil Citrate), you should tell your doctor if you are currently taking any of the following drugs:

• Other drugs that treat impotence or erectile dysfunction, such as alprostradil (common names Muse, Caverject or Edex), or yohimbine (common names Yocon, Yodoxin or others)
• Erythromycin, which is an antibiotic (Common names Eryc, E-Mycin, Ery-Tab and others) or clarithromycin (Biaxin), which is also an antibiotic
• HIV medications, such as ritonavir (Norvir), indinavir (Crixivan), amprenavir (Agenerase), nelfinavir (Vracept), saquinavir (Fortovase or Invierase), delavirdine (Rescriptor) or any others
• Anti-fungal medications, such as itraconazole (common name Sporanox) or ketoconazole (Nizoral)
• Phenobarbital (Luminal)
• Cimetidine (Tagamet or Tagamet HB)
• Rifabutin (Mycobutin) or rifampin (Rifamate or Rifadin)
• Carbamazepine (Tegretol) or phenytoin (Dilantin)

If you are on any of these medications, you may not be able to take Viagra Professional (Sildenafil Citrate) or you may need a dosage adjustment or special monitoring. This is why it is important to inform your doctor of all drugs you are currently taking to make sure that Viagra Professional (Sildenafil Citrate) is right for you. Ask your doctor, pharmacist or nurse about any further information about Viagra Professional (Sildenafil Citrate).

Possible side effects of Viagra Professional (Sildenafil Citrate) are:

• Headache
• Flushing
• Stomach upset
• Nasal stuffiness
• Diarrhea
• Dizziness

If these effects persist or worsen, notify your doctor promptly.

Also notify your doctor promptly if you experience any of the following unlikely side effects:

• Painful or other urination problems
• Vision problems
• Skin rash

The following side effects are very unlikely, but again notify your doctor immediately should you experience them:

• Chest pain
• Fainting
• Swelling of the foot or ankle

If you experience a painful or prolonged erection (that lasts longer than 4 hours), you should stop using Viagra Professional (Sildenafil Citrate) and seek immediate medical attention. If you notice other effects not listed above, contact your doctor or pharmacist.