What Is Phentolamine Mesylate?

The medication known as phentolamine mesylate reverses anesthesia and hypertension. Alpha blocking, or alpha-adrenergic antagonist medications, treat a variety of conditions by relaxing tissue. The physiological effects of the medication, which include cardiac involvement, restrict its use to patients aged six and older. Pharmaceutical companies also caution against using the compound on patients with a history of heart disease. Physicians typically administer the medication by injection in clinical or hospital settings. Oral forms of the alpha blocking medications that are commonly prescribed include doxazosin, tamsulosin and terazosin.

Phentolamine mesylate belongs to the group of medications known as alpha-blockers. The alpha-adrenergic blocking medications bind to alpha 1-receptor sites and inhibit the hormone norepinephrine, producing muscle relaxation. This usually affects organ musculature, which includes the heart, along with the smooth muscle of blood vessels. Risks of affecting the cardiac muscle include the possibility of altering the heart rate and the force of the contractions. Patients may experience slower or faster than normal heart rates, and phentolamine mesylate might induce cardiac dysrhythmias.

Some risks are more frequently associated with intramuscular (IM) and intravenous (IV) injections of phentolamine mesylate and include the possibility of experiencing a heart attack, as patients suffer shock-like symptoms from severe hypotension. The medication may also produce cerebrovascular spasms or blockages. Common phentolamine mesylate side effects include injection site pain and headaches. Dizziness, generalized weakness, and orthostatic hypotension might occur, and some patients complain of diarrhea accompanied by abdominal pain, facial swelling, and hypertension.

Uses of phentolamine mesylate include reversing the localized anesthetic effects on oral tissues following dental procedures. Oral surgeons typically inject the medication into the same sites used for numbing agents. Some patients have a condition known as pheochromocytoma, meaning tumor development on the adrenal glands. Stress, especially before and during medical procedures, causes hypertensive reactions in these individuals. Physicians might administer the short acting alpha-blocker IM or IV, which reverses the symptoms of hypertension by causing vasodilatation.

Health care providers might also administer phentolamine mesylate simultaneously with norepinephrine. The hormone notoriously causes tissue damage at the injection site and the alpha-blocker prevents this occurrence. Uses of alpha-blockers in general may include alleviation of symptoms associated with an enlarged prostate, by relaxing the bladder and increasing urine output. Relaxation of vascular smooth muscle improves blood flow in circulatory conditions that include Reynaud’s phenomena. Physicians sometimes use the medication as treatment for the hardening and thickening of skin experienced by patients diagnosed with scleroderma.