I have a phobia of people when there's a crowd my stomach started getting tighter and i feel i'm going to vomit.is there any medication to stop this.

Doctor or counselor: You may need to be evaluated for medical causes but therapy can help, see a doctor for more thorough discussion, causes & treatment options.

Anxiety: Yes, not just the medication, behavioral treatment also helps, for a long term benefit consider behavioral therapy, may use medicine in addition if necessary.

Agoraphobia: A form of panic disorder. Cognitive behavioral therapy +/- SSRI or serotonin selective reuptake inhibitor, are most frequently used in treatment. Talk to your doc about your symptoms.

See a therapist/psyc: Sounds like social anxiety. You may benefit from talk therapy. In some cases, symptoms may respond to prophylactic Beta Blockers. Johnny Carson and many performers had/have a form of this.

Phobia in crowds: Fear of crowds is a form of agoraphobia. Consider therapy to discuss the triggers etiology , coping mechanisms. techniques. Medications as SSRIs, like Paxil ,Zoloft ,Effexor (venlafaxine) have been used as have the tranquilizers as Xanax, Klonopin. Beta blockers like propanolol have use in acute encounters like public speaking Discuss your situation with a doctor/urgent care for a referral.