General synonyms:
* Suffocating: This is a very similar word to stifling, often used to describe a feeling of breathlessness or lack of air.
* Oppressive: This word emphasizes the feeling of being weighed down or burdened.
* Choking: This word suggests a feeling of being unable to breathe or express oneself freely.
* Restrictive: This word emphasizes the feeling of being limited or confined.
* Repressive: This word suggests a feeling of being controlled or suppressed.
More specific synonyms:
* Throttling: This word suggests a feeling of being choked or strangled.
* Gagging: This word implies a feeling of being unable to speak or express oneself.
* Claustrophobic: This word describes a feeling of being trapped or confined in a small space.
* Inhibiting: This word emphasizes the feeling of being prevented from developing or growing.
The best word to use will depend on the specific context and the nuance you want to convey.