Protein powders and bars

What Retro said. Some things that cause constipation - which MAY be a first step on the road to impacted bowel if persistent - are too little fiber (ultra common), under-hydration (somewhat common), too little fat in the diet (not common, except when people try to eat very too low fat during weight loss).

High protein, within reason, is OK. What does "within reason" mean? It means not eating so much protein that we don't get enough fiber, fats, essential and beneficial micronutrients, or other needful nutrition.

How much protein are you getting, overall? A shake or a bar would be fine, for most people . . . maybe even necessary. Protein up to nearly gram per pound of ideal body weight per day is generally considered safe for most people per research, and more can be acceptable in certain circumstances.

Here's a quote from the abstract of a review in the journal Food & Function that's pretty representative of what I've seen:

Based on short-term nitrogen balance studies, the Recommended Dietary Allowance of protein for a healthy adult with minimal physical activity is currently 0.8 g protein per kg body weight (BW) per day. To meet the functional needs such as promoting skeletal-muscle protein accretion and physical strength, dietary intake of 1.0, 1.3, and 1.6 g protein per kg BW per day is recommended for individuals with minimal, moderate, and intense physical activity, respectively. Long-term consumption of protein at 2 g per kg BW per day is safe for healthy adults, and the tolerable upper limit is 3.5 g per kg BW per day for well-adapted subjects. Chronic high protein intake (>2 g per kg BW per day for adults) may result in digestive, renal, and vascular abnormalities and should be avoided.

That's for healthy people. People with certain health conditions or risks, such as kidney disease, may be advised to limit protein intake, but even they need some. Toward the top end of the range for healthy people, i.e., that 2g/kg and more, there's still some disagreement about needs and risks. For sure, individual circumstances matter.

Too-low protein isn't ideal for health, either.