Somewhere in canon I recall reading that people on Fast Drug can be housed in low berths without activating the suspension cycle.
One requirement for the use of Fast Drug would probably be diapers. Other than that, the main result of the drug suspension would be the hunger of a subjective full day without food, plus the aches of 60 days of physical inactivity.
The historical reasons for the presence of both Fast Drug and low berths in Traveller canon are pretty clear -- editorial deadlines in the classic edition's publishing schedule, followed by the inertia of canon. But the in-universe explanation is not as obvious; it takes some hand-waving to bring them into line with each other.
One reasonable explanation for the unpopularity of Fast Drug travel is that the aches from 60 days of inactivity are really unpleasant, and leave the person unable to function well for some time after revival. And by contrast, low berths are as safe as jump travel itself as long as revival is attended by a medic, and once the revival is completed the person is ready to go, including rushing off to battle stations for Frozen Watch crew.
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Slow Drug and Medical Slow are another interesting question. The combat version has documented restrictions: it hurts when it wears off (hit points in game mechanics).
Medical Slow doesn't have documented problems, but doing 30 days of healing in a day would be tremendously costly in terms of calorie expenditure. Even without the drug, healing can be metabolically expensive; one risk people face in present day burn units is the possibility that healing will cost so many calories that the patient suffers from starvation. Accelerate that 30 to one and it's a big deal.
To make Medical Slow usable, the patient would probably have to be fed lots of intravenous nutrients -- sugars for energy and protein and micronutrients for the physical components of the healed tissues. Additionally, the patient would probably need a high oxygen partial pressure to help supply the oxygen needed for the healing.
How much higher are the metabolic requirements? A human at rest uses the equivalent of about 1200 kcal per day, about 20% of which is for the brain, and at rest means minimal voluntary muscle activity by definition. A human doing extreme athletics (an example I read was cross country skiing across Antarctica) can use 6000 to 10000 kcal per day. A patient in a burn unit can use up to 10000 kcal per day. From that we can guess that 10000 kcal per day is about the limit of human respiration without supplemental oxygen, assuming that's the limiting factor. Breathing pure oxygen could increase that by a factor of five, assuming liters of oxygen per breath is the limiting factor; a pressure chamber could increase it further, so hypothetically six atmospheres of pure oxygen would supply the needed 30 times as much respiration.
Another limitation is heat dissipation. To remove waste heat in a state of greatly amplified metabolism would probably require a chill bath and body temperature monitoring.
But not all healing is as calorie intensive as a burn unit. Maybe the limit isn't 30 times the maximum human metabolism -- 30×10000 kcal per day -- but 30 times the typical metabolism of a moderately active person -- 30×2000 kcal per day. That would still require the high partial pressure oxygen and active heat removal, but it doesn't stretch reality quite as much.
But 60000 kcal per day of nutrition and six times normal oxygen is still something that can only happen under intense medical supervision. Don't use the stuff unless the patient is under constant care of a nurse, with a doctor checking in once or twice per hour.
