Pseudotumor cerebri (PTC) is a neurological side effect that has recently been linked to hormonal birth control products. This condition, which often presents like a brain tumor, is caused by sudden increased pressure in the brain (intracranial pressure). Symptoms of pseudotumor cerebri include headache, blurred or double vision, ringing of the ears, and papilledema (swelling of the optic nerve).
What is Implanon?
Implanon is a flexible plastic implant about the size of a cardboard matchstick. The device is inserted by a doctor under the skin of a woman’s upper arm. It protects against pregnancy for up to 3 years. Implanon is manufactured by Merck & Co., and was approved by the U.S. Food & Drug Administration (FDA) in July 2006.
What is Pseudotumor Cerebri?
Pseudotumor cerebri is characterized by abnormally high intracranial pressure that causes symptoms similar to that of a brain tumor. The disorder occurs when excessive amounts of cerebrospinal fluid accumulate in the brain, which may be caused by an increase in fluid production or decrease in fluid absorption. PTC may also be referred to as idiopathic intracranial hypertension (IIH) or benign intracranial hypertension (BIH).
Hormonal Birth Control and PTC
It is still not clearly understood why pseudotumor cerebri occurs. However, some medications including hormonal contraceptives have been associated with the disorder. One hormone in particular, levonorgestrel, was linked to pseudotumor cerebri in 1995. Levonorgestrel is a second-generation synthetic progestin, and is the most widely-prescribed contraceptive progestin worldwide.
Signs and symptoms of pseudotumor cerebri may include:
- Changes in vision
- Vision loss
- Papilledema (swelling of the optic nerve)
- Feeling dizzy or nauseated
- Neck stiffness
- Difficulty walking
- Persistent ringing in the ears (tinnitus)
How is Pseudotumor Cerebri Diagnosed?
A physical exam and diagnostic tests can help diagnose PTC and rule out a brain tumor.
The following tests may be performed to confirm the diagnosis:
- Magnetic resonance imaging (MRI) or computerized tomography (CT) scans of the brain
- Spinal tap (also called a lumbar puncture)
- Eye exam