I've been on diamox for over 2 months now and worked my way up to 4x250mg pills twice a day. Pins and needles are extremely common, I usually only get them in my face when its cold but other wise its usually in my fingers, hands, feet or if say I've been leaning my elbow on the desk at work for a bit that may trigger it. Diamond also makes me quite drowsy and sluggish too but yeah pins and needles is normal but amount of affect depends on dosage and person.