sorry I meant carry on..its been a long day! I fixed my OP.
I found this on the TSA website...
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.
Additional 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.
For more information on these measures, please read our memo outlining our policy. Changes in Allowances for Persons with Disabilities at Airport Security Checkpoints (pdf, 101kb)
Non-liquid or gel medications of all kinds such as solid pills, or inhalers are allowed through the security checkpoint once they have been screened. We recommend, but do not require, that your medications be labeled to assist with the screening process.
Checked luggage or carry-on luggage??
The baggie rule (as far as I've ever seen) refers only to carry-on luggage. I'd never put any medication in my checked luggage (you never know if it may get delayed).
For carry-on luggage, only liquids/gels go in your baggie. I always use a 1L baggie. I would think the dimensions you described for the smaller baggie would fine. Almost all the airports I've flown out of recently have baggies available just before security, so if they have an issue with your baggie, you could always get a new one (NB - I do not promise/suggest that your airport will have baggies).