Papaverine is in a class of drugs called vasodilators. Papaverine relaxes veins and arteries, which makes them wider and allows blood to pass through them more easily. These actions may help to increase the amount of oxygen-rich blood in your brain, heart, and muscles.

Papaverine may also be useful in treating conditions involving spasms of the intestines and urinary tract.

Papaverine may also be used for purposes other than those listed in this medication guide.

Use caution when driving, operating machinery, or performing other hazardous activities. Papaverine may cause dizziness. If you experience dizziness, avoid these activities.

If you experience dizziness, rise slowly from a sitting or lying position to avoid falling.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while you are taking papaverine.

Notify your doctor if you experience especially bothersome sweating, rash, flushing, headache, tiredness, yellowing of your skin, nausea, decreased appetite, diarrhea, or constipation.

Before taking this medication, tell your doctor if you have

• heart disease or irregular heartbeats,

• liver disease,

• glaucoma, or

• Parkinson's disease.

You may not be able to take papaverine, or you may require a lower dose or special monitoring during treatment if you have any of the conditions listed above.

Papaverine is in the FDA pregnancy category C. This means that it is not known whether papaverine will harm an unborn baby. Do not take papaverine without first talking to your doctor if you are pregnant.

It is not known whether papaverine passes into breast milk. Do not take this medication without first talking to your doctor if you are breast-feeding a baby.