To take it a step further, I would argue that it is not limited to 4 oz either.

From here: http://www.tsa.gov/travelers/airtrav...rial_1059.shtm

You may bring all prescription and over-the-counter medications (liquids, gels, and aerosols) including KY jelly, eye drops, and saline solution for medical purposes.

Additonal items you may bring include:

- Liquids including water, juice, or liquid nutrition or gels for passengers with a disability or medical condition;
- Life-support and life-sustaining liquids such as bone marrow, blood products, and transplant organs;
- Items used to augment the body for medical or cosmetic reasons such as mastectomy products, prosthetic breasts, bras or shells containing gels, saline solution, or other liquids; and,
- Gels or frozen liquids needed to cool disability or medically related items used by persons with disabilities or medical conditions.

You are not limited in the amount or volume of these items you may bring in your carry-on baggage. BUT if the medically necessary items exceed 3 ounces or are not contained in a one-quart, zip-top plastic bag, you MUST declare to one of our Security Officers at the checkpoint for further inspection.

We normally X-ray medication and related supplies. However, as a customer service, you may ask that Security Officers visually inspect your medication and associated supplies.

You must ask for visual inspection before the screening process begins; otherwise your medications and supplies will be X-rayed.

If you would like to take advantage of this option, please have your medication and associated supplies separated from your other property in a separate pouch/bag when you approach the Security Officer at the walk-through metal detector.

Ask the Security Officer to visually inspect your medication and hand your medication pouch/bag to him or her.

To prevent your medication, associated supplies or fragile medical materials for contamination or damage, we will ask you to display, handle, and repack your own medication and associated supplies during visual inspection.

Any medication and/or associated supplies that we can’t clear visually will be X-rayed. If you refuse, you will not be permitted to carry your medications and related supplies into the sterile area.